



COSE                                                       H. Tschofenig
Internet-Draft                                                     H-BRS
Intended status: Standards Track                          O. Steele, Ed.
Expires: 3 September 2026                                   Tradeverifyd
                                                              D. Ajitomi
                                                                 bibital
                                                            L. Lundblade
                                                     Security Theory LLC
                                                                M. Jones
                                                  Self-Issued Consulting
                                                            2 March 2026


Use of Hybrid Public-Key Encryption (HPKE) with CBOR Object Signing and
                           Encryption (COSE)
                        draft-ietf-cose-hpke-23

Abstract

   This specification defines hybrid public-key encryption (HPKE) for
   use with CBOR Object Signing and Encryption (COSE).  HPKE offers a
   variant of public-key encryption of arbitrary-sized plaintexts for a
   recipient public key.

   HPKE is a general encryption framework utilizing an asymmetric key
   encapsulation mechanism (KEM), a key derivation function (KDF), and
   an Authenticated Encryption with Associated Data (AEAD) algorithm.

   This document defines the use of HPKE with COSE.  Authentication for
   HPKE in COSE is provided by COSE-native security mechanisms or by the
   pre-shared key authenticated variant of HPKE.

Discussion Venues

   This note is to be removed before publishing as an RFC.

   Discussion of this document takes place on the CBOR Object Signing
   and Encryption Working Group mailing list (cose@ietf.org), which is
   archived at https://mailarchive.ietf.org/arch/browse/cose/.

   Source for this draft and an issue tracker can be found at
   https://github.com/cose-wg/draft-ietf-cose-hpke.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.




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Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
   2.  Conventions and Terminology . . . . . . . . . . . . . . . . .   4
   3.  HPKE for COSE . . . . . . . . . . . . . . . . . . . . . . . .   5
     3.1.  Overview  . . . . . . . . . . . . . . . . . . . . . . . .   5
     3.2.  HPKE Integrated Encryption Mode . . . . . . . . . . . . .   5
     3.3.  HPKE Key Encryption Mode  . . . . . . . . . . . . . . . .   7
       3.3.1.  Recipient_structure . . . . . . . . . . . . . . . . .   8
       3.3.2.  COSE-HPKE Recipient Construction  . . . . . . . . . .   9



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       3.3.3.  Security Design Rationale . . . . . . . . . . . . . .  10
     3.4.  Key Representation  . . . . . . . . . . . . . . . . . . .  11
   4.  Ciphersuite Registration  . . . . . . . . . . . . . . . . . .  12
     4.1.  COSE_Keys for COSE-HPKE Ciphersuites  . . . . . . . . . .  14
   5.  Examples  . . . . . . . . . . . . . . . . . . . . . . . . . .  14
     5.1.  COSE HPKE Integrated Encryption Mode  . . . . . . . . . .  15
     5.2.  COSE HPKE Key Encryption Mode . . . . . . . . . . . . . .  16
     5.3.  Key Representation  . . . . . . . . . . . . . . . . . . .  17
       5.3.1.  Public Key for HPKE-0 . . . . . . . . . . . . . . . .  17
       5.3.2.  Private Key for HPKE-0  . . . . . . . . . . . . . . .  18
       5.3.3.  KEM Public Key for HPKE-4 . . . . . . . . . . . . . .  18
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .  19
   7.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  19
     7.1.  COSE Algorithms Registry  . . . . . . . . . . . . . . . .  20
       7.1.1.  HPKE-0  . . . . . . . . . . . . . . . . . . . . . . .  20
       7.1.2.  HPKE-1  . . . . . . . . . . . . . . . . . . . . . . .  20
       7.1.3.  HPKE-2  . . . . . . . . . . . . . . . . . . . . . . .  20
       7.1.4.  HPKE-3  . . . . . . . . . . . . . . . . . . . . . . .  21
       7.1.5.  HPKE-4  . . . . . . . . . . . . . . . . . . . . . . .  21
       7.1.6.  HPKE-5  . . . . . . . . . . . . . . . . . . . . . . .  21
       7.1.7.  HPKE-6  . . . . . . . . . . . . . . . . . . . . . . .  22
       7.1.8.  HPKE-7  . . . . . . . . . . . . . . . . . . . . . . .  22
       7.1.9.  HPKE-0-KE . . . . . . . . . . . . . . . . . . . . . .  22
       7.1.10. HPKE-1-KE . . . . . . . . . . . . . . . . . . . . . .  23
       7.1.11. HPKE-2-KE . . . . . . . . . . . . . . . . . . . . . .  23
       7.1.12. HPKE-3-KE . . . . . . . . . . . . . . . . . . . . . .  23
       7.1.13. HPKE-4-KE . . . . . . . . . . . . . . . . . . . . . .  24
       7.1.14. HPKE-5-KE . . . . . . . . . . . . . . . . . . . . . .  24
       7.1.15. HPKE-6-KE . . . . . . . . . . . . . . . . . . . . . .  25
       7.1.16. HPKE-7-KE . . . . . . . . . . . . . . . . . . . . . .  25
     7.2.  COSE Header Parameters  . . . . . . . . . . . . . . . . .  25
       7.2.1.  ek Header Parameter . . . . . . . . . . . . . . . . .  25
       7.2.2.  psk_id Header Parameter . . . . . . . . . . . . . . .  26
   8.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  26
     8.1.  Normative References  . . . . . . . . . . . . . . . . . .  26
     8.2.  Informative References  . . . . . . . . . . . . . . . . .  27
   Appendix A.  Contributors . . . . . . . . . . . . . . . . . . . .  27
   Appendix B.  Acknowledgements . . . . . . . . . . . . . . . . . .  28
   Appendix C.  Testvectors  . . . . . . . . . . . . . . . . . . . .  28
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  76

1.  Introduction

   Hybrid public-key encryption (HPKE) [I-D.ietf-hpke-hpke] is a scheme
   that provides public key encryption of arbitrary-sized plaintexts
   given a recipient's public key.





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   This document defines the use of HPKE with COSE ([RFC9052],
   [RFC9053]) with the single-shot APIs defined in Section 6 of
   [I-D.ietf-hpke-hpke].  Multiple invocations of Open() / Seal() on the
   same context, as discussed in Section 9.7.1 of [I-D.ietf-hpke-hpke]
   are not supported.

   Algorithm identifiers follow a ciphersuite scheme in which a single
   COSE algorithm ID maps to the three algorithm IDs required for HPKE:
   the Key Encapsulation Mechanism (KEM), the Key Derivation Function
   (KDF), and the Authenticated Encryption with Associated Data (AEAD)
   algorithm.

2.  Conventions and Terminology

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in
   BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.

   This specification uses the following abbreviations and terms:

   *  Content-encryption key (CEK), as described in Section 2 of
      [RFC9052].

   *  Hybrid Public Key Encryption (HPKE) as defined in
      [I-D.ietf-hpke-hpke].

   *  pkR is the public key of the recipient, as defined in
      [I-D.ietf-hpke-hpke].

   *  skR is the private key of the recipient, as defined in
      [I-D.ietf-hpke-hpke].

   *  Key Encapsulation Mechanism (KEM), see [I-D.ietf-hpke-hpke].

   *  Key Derivation Function (KDF), see [I-D.ietf-hpke-hpke].

   *  Authenticated Encryption with Associated Data (AEAD), see
      [I-D.ietf-hpke-hpke].

   *  Additional Authenticated Data (AAD), see [I-D.ietf-hpke-hpke].









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3.  HPKE for COSE

3.1.  Overview

   This specification supports two modes of using HPKE in COSE, namely:

   *  HPKE Integrated Encryption mode, where HPKE is used to encrypt the
      plaintext.  This mode can only be used with a single recipient.
      Section 3.2 provides the details.

   *  HPKE Key Encryption mode, where HPKE is used to encrypt a content
      encryption key (CEK), which then encrypts the content.  This mode
      supports multiple recipients.  Section 3.3 provides the details.

   Distinct algorithm identifiers are defined and registered that are
   specific to each COSE HPKE mode so that they are fully specified, as
   required by [RFC9864].  Algorithm identifiers MUST only be used in
   the COSE HPKE mode that is specified for them.

   In both cases, the new COSE header parameter "ek" MUST be present.
   It contains the encapsulated KEM shared secret.  The value of this
   parameter MUST be the "enc" value output by the HPKE Seal()
   operation, as defined in Section 6.1 of [I-D.ietf-hpke-hpke].  The
   "ek" header parameter MUST be encoded as a CBOR byte string.

   HPKE defines several authentication modes, as described in Table 1 of
   [I-D.ietf-hpke-hpke].  This specification uses both 'mode_base' and
   'mode_psk'.  The mode is 'mode_psk' if the "psk_id" header parameter
   is present; otherwise, the mode defaults to 'mode_base'. 'mode_base'
   is described in Section 5.1.1 of [I-D.ietf-hpke-hpke], which only
   enables encryption to the holder of a given KEM private key.
   'mode_psk' is described in Section 5.1.2 of [I-D.ietf-hpke-hpke],
   which authenticates using a pre-shared key.

3.2.  HPKE Integrated Encryption Mode

   This mode applies if the COSE_Encrypt0 structure uses a COSE-HPKE
   algorithm and has no recipient structure(s).

   Because COSE-HPKE supports header protection, if the "alg" parameter
   is present, it MUST be included in the protected header and MUST be a
   COSE-HPKE algorithm.









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   Although the use of the "kid" parameter in COSE_Encrypt0 is
   discouraged by RFC 9052, this document RECOMMENDS the use of the
   "kid" parameter (or other parameters) to explicitly identify the
   static recipient public key used by the sender.  If the COSE_Encrypt0
   structure includes a "kid" parameter, the recipient MAY use it to
   select the corresponding private key.

   When encrypting, the inputs to the HPKE Seal operation are set as
   follows:

   *  kem_id: From the ciphersuite.  See Section 4.

   *  pkR: The recipient public key, converted into an HPKE public key.

   *  kdf_id: From the ciphersuite.  See Section 4.

   *  info: Defaults to the empty string; externally provided
      information MAY be used instead.

   *  aad: MUST contain the byte string for the authenticated data
      structure according to the steps defined in Section 5.3 of RFC
      9052.

   For the Integrated Encryption mode the context string will be
   "Encrypt0".  Externally provided AAD information MAY be provided and
   MUST be passed into the Enc_structure via the external_aad field.

   *  aead_id: From the ciphersuite.  See Section 4.

   *  pt: The raw message plaintext.

   The outputs are used as follows:

   *  enc: MUST be placed raw into the "ek" (encapsulated key) parameter
      in the unprotected bucket.

   *  ct: MUST be used as layer ciphertext.  If not using detached
      content, this is directly placed as ciphertext in COSE_Encrypt0
      structure.  Otherwise, it is transported separately and the
      ciphertext field is nil.  See Section 5 of [RFC9052] for a
      description of detached payloads.

   If 'mode_psk' has been selected, then the "psk_id" parameter MUST be
   present.  If 'mode_base' has been chosen, then the "psk_id" parameter
   MUST NOT be present.

   When decrypting, the inputs to the HPKE Open operation are set as
   follows:



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   *  kem_id: From the ciphersuite.  See Section 4.

   *  skR: The recipient private key, converted into an HPKE private
      key.

   *  kdf_id: From the ciphersuite.  See Section 4.

   *  aead_id: From the ciphersuite.  See Section 4.

   *  info: Defaults to the empty string; externally provided
      information MAY be used instead.

   *  aad: MUST contain the byte string for the authenticated data
      structure according to the steps defined in Section 5.3 of RFC
      9052.  For the Integrated Encryption mode the context string will
      be "Encrypt0".  Externally provided AAD information MAY be
      provided and MUST be passed into the Enc_structure via the
      external_aad field.

   *  enc: The contents of the layer "ek" parameter.

   *  ct: The contents of the layer ciphertext.

   The plaintext output is the raw message plaintext.

   The COSE_Encrypt0 MAY be tagged or untagged.

   An example is shown in Section 5.1.

3.3.  HPKE Key Encryption Mode

   This mode specifies a method for constructing a COSE_Recipient using
   HPKE.  In this construction, both key agreement and key wrapping are
   performed within HPKE.

   A COSE_Encrypt structure is used with two logical layers:

   *  Layer 0 contains the content (plaintext) encrypted with the CEK.
      This ciphertext may be detached, and if not detached, then it is
      included in the COSE_Encrypt structure.

   *  Layer 1 contains a COSE_Recipient with the parameters needed for
      HPKE to generate a shared secret used to encrypt the CEK.  This
      layer conveys the encrypted CEK in the COSE_recipient structure
      using a COSE-HPKE algorithm.






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   This two-layer structure is used to encrypt content that can also be
   shared with multiple recipients at the expense of a single additional
   encryption operation.  The content is encrypted once with the CEK,
   then the CEK is encrypted for each recipient.  Layer 1 may also
   contain other COSE_Recipients using other content key distribution
   methods that also encrypt the CEK.

3.3.1.  Recipient_structure

   This section defines the Recipient_structure, which is used in place
   of COSE_KDF_Context for COSE-HPKE recipients.  It MUST be used for
   COSE-HPKE recipients, as it provides integrity protection for
   recipient-protected header parameters.

   The Recipient_structure is modeled after the Enc_structure defined in
   [RFC9052], but is specific to COSE_recipient structures and MUST NOT
   be used with COSE_Encrypt.

   Furthermore, the use of COSE_KDF_Context is prohibited in COSE-HPKE;
   it MUST NOT be used.

   Recipient_structure = [
       context: "HPKE Recipient",
       next_layer_alg: int/tstr,
       recipient_protected_header: empty_or_serialized_map,
       recipient_extra_info: bstr
   ]

   "next_layer_alg":  The algorithm ID of the COSE layer for which the
      COSE_recipient is encrypting a key.  It is the algorithm that the
      key MUST be used with.  This value MUST match the "alg" parameter
      in the next lower COSE layer.

   "recipient_protected_header":  The protected header parameters from
      the COSE_recipient.

   "recipient_extra_info":  Any additional context the application
      wishes to include in the key derivation via the HPKE info
      parameter.  If none, it is a zero-length string.

   The Recipient_structure MUST be serialized deterministically in
   accordance with the Core Deterministic Encoding Requirements defined
   in Section 4.2.1 of [RFC8949].  This requirement applies only to the
   Recipient_structure itself — the array and its four members.  It does
   not extend into the byte-string wrapped protected headers.






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3.3.2.  COSE-HPKE Recipient Construction

   This section gives the steps for constructing a COSE_Recipient using
   HPKE.

   When encrypting, the inputs to the HPKE Seal operation are set as
   follows:

   *  kem_id: From the ciphersuite.  See Section 4.

   *  kdf_id: From the ciphersuite.  See Section 4.

   *  aead_id: From the ciphersuite.  See Section 4.

   *  pkR: The recipient public key, converted into HPKE public key.

   *  info: Deterministic encoding of the Recipient_structure.
      Externally provided context information MAY be provided and MUST
      be passed into the Recipient_structure via the
      recipient_extra_info field.

   *  aad: Defaults to the empty string; externally provided information
      MAY be used instead.

   *  pt: The CEK.

   The outputs are put in the COSE_Recipient as follows:

   *  enc: MUST be placed into the "ek" (encapsulated key) header
      parameter in the unprotected bucket.

   *  ct: MUST be placed in the ciphertext field.

   While the "alg" header parameter is not strictly required in the
   COSE_Recipient, if present, it must be the ciphersuite used to
   specify the HPKE algorithms.  See Section 4.  If the "alg" parameter
   is present it MUST be a protected header parameter.

   The protected header MAY contain the "kid" parameter to identify the
   static recipient public key that the sender used.  Use of the "kid"
   parameter is RECOMMENDED to explicitly identify the static recipient
   public key used by the sender.  Including it in the protected header
   parameters ensures that it is input into the key derivation function
   of HPKE.

   When decrypting, the inputs to the HPKE Open operation are as
   follows:




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   *  kdf_id: From the "alg" parameter ciphersuite.  See Section 4.

   *  aead_id: From the "alg" parameter ciphersuite.  See Section 4.

   *  kem_id: From the "alg" parameter ciphersuite.  See Section 4.

   *  enc: From the "ek" parameter in the COSE_Recipient headers.

   *  skR: The recipient private key, converted into an HPKE private
      key.

   *  info: Deterministic encoding of the Recipient_structure.
      Externally provided context information MAY be provided and MUST
      be passed into the Recipient_structure via the
      recipient_extra_info field.

   *  aad: Defaults to the empty string; externally provided information
      MAY be used instead.

   *  ct: The contents of the COSE_Recipient ciphertext field.

   The plaintext output is the CEK.

   It is not necessary to populate recipient_aad, as HPKE inherently
   mitigates the classes of attacks that COSE_KDF_Context, and SP800-56A
   are designed to address.  COSE-HPKE use cases may still utilize
   recipient_aad for other purposes as needed; however, it is generally
   intended for small values such as identifiers, contextual
   information, or secrets.  It is not designed for protecting large or
   bulk external data.

   Any bulk external data that requires protection should be handled at
   layer 0 using external_aad.

   The COSE_recipient structure is computed for each recipient.

   When encrypting the content at layer 0, the instructions in
   Section 5.3 of [RFC9052] MUST be followed, including the calculation
   of the authenticated data structure.

   An example is shown in Section 5.2.

3.3.3.  Security Design Rationale

   COSE-HPKE does not use COSE_KDF_Context, which is defined in
   Section 5.2 of [RFC9053], for the following reasons:





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   *  HPKE is a well-analyzed and widely reviewed construction that
      already incorporates the protections provided by COSE_KDF_Context.

   *  The HPKE design avoids many of the weaknesses present in earlier
      key agreement protocols that COSE_KDF_Context was designed to
      mitigate.

   *  Use of the COSE_KDF_Context would introduce unnecessary
      complexity; many of the fields typically go unused.

   *  It is difficult to know what to put in the COSE_KDF_Context
      fields.

   The algorithm identifier for the bulk content encryption algorithm
   can be manipulated, since it is neither integrity-protected nor
   incorporated into the key derivation.  In particular, the layer 0
   algorithm identifier is not integrity protected by the COSE_Recipient
   and is therefore not cryptographically bound to the key agreement
   algorithm.  This class of attack has been demonstrated against CMS; a
   corresponding mitigation is described in
   [I-D.ietf-lamps-cms-cek-hkdf-sha256].

   The "next_layer_alg" member of the Recipient_structure mitigates this
   attack by explicitly binding the bulk content encryption algorithm
   identifier with the COSE_Recipient.  The "next_layer_alg" member is
   explicitly defined to identify the algorithm for the immediately
   following COSE layer.  Such explicit layering semantics were not
   provided for the AlgorithmID field in COSE_KDF_Context, where the
   intended interpretation was ambiguous.

3.4.  Key Representation

   The COSE_Key with the existing key types can be used to represent KEM
   private or public keys.  When using a COSE_Key for COSE-HPKE, the
   following checks are made:

   *  If the "kty" field is "AKP", then the public and private keys
      SHALL be the raw HPKE public and private keys (respectively) for
      the KEM used by the algorithm.

   *  Otherwise, the key MUST be suitable for the KEM used by the
      algorithm.  In case the "kty" parameter is "EC2" or "OKP", this
      means the value of "crv" parameter is suitable.  The valid
      combinations of KEM, "kty" and "crv" for the algorithms defined in
      this document are shown in Figure 1.

   *  If the "key_ops" field is present, it MUST include only "derive
      bits" for the private key and MUST be empty for the public key.



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   Examples of the COSE_Key for COSE-HPKE are shown in Section 5.3.

4.  Ciphersuite Registration

   A ciphersuite is a set of cryptographic algorithms selected to
   achieve a specific security level.  For COSE-HPKE, a single COSE
   algorithm ID represents a ciphersuite that maps to the following HPKE
   algorithm identifiers:

   *  KEM algorithm

   *  KDF algorithm

   *  AEAD algorithm

   Each COSE algorithm ID registered for COSE-HPKE MUST indicate the
   three HPKE algorithm IDs mapped by the ciphersuite.

   The HPKE mode is determined by the presence or absence of the
   "psk_id" parameter and is therefore not explicitly indicated in the
   ciphersuite.

   For a list of ciphersuite registrations, please see Section 7.  The
   following table summarizes the relationship between the ciphersuites
   registered in this document and the values registered in the HPKE
   IANA registry [HPKE-IANA].

   +-------------------+-----------------------+-------------------+
   | COSE-HPKE         | COSE HPKE Mode        |        HPKE       |
   | Ciphersuite Label |                       | KEM  | KDF | AEAD |
   +-------------------+-----------------------+------+-----+------+
   | HPKE-0            | Integrated Encryption | 0x10 | 0x1 | 0x1  |
   | HPKE-1            | Integrated Encryption | 0x11 | 0x2 | 0x2  |
   | HPKE-2            | Integrated Encryption | 0x12 | 0x3 | 0x2  |
   | HPKE-3            | Integrated Encryption | 0x20 | 0x1 | 0x1  |
   | HPKE-4            | Integrated Encryption | 0x20 | 0x1 | 0x3  |
   | HPKE-5            | Integrated Encryption | 0x21 | 0x3 | 0x2  |
   | HPKE-6            | Integrated Encryption | 0x21 | 0x3 | 0x3  |
   | HPKE-7            | Integrated Encryption | 0x10 | 0x1 | 0x2  |
   | HPKE-0-KE         | Key Encryption        | 0x10 | 0x1 | 0x1  |
   | HPKE-1-KE         | Key Encryption        | 0x11 | 0x2 | 0x2  |
   | HPKE-2-KE         | Key Encryption        | 0x12 | 0x3 | 0x2  |
   | HPKE-3-KE         | Key Encryption        | 0x20 | 0x1 | 0x1  |
   | HPKE-4-KE         | Key Encryption        | 0x20 | 0x1 | 0x3  |
   | HPKE-5-KE         | Key Encryption        | 0x21 | 0x3 | 0x2  |
   | HPKE-6-KE         | Key Encryption        | 0x21 | 0x3 | 0x3  |
   | HPKE-7-KE         | Key Encryption        | 0x10 | 0x1 | 0x2  |
   +-------------------+-----------------------+------+-----+------+



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   The following list maps the ciphersuite labels to their textual
   description.

   *  HPKE-0: Integrated Encryption with DHKEM(P-256, HKDF-SHA256) KEM,
      HKDF-SHA256 KDF, and AES-128-GCM AEAD.

   *  HPKE-1: Integrated Encryption with DHKEM(P-384, HKDF-SHA384) KEM,
      HKDF-SHA384 KDF, and AES-256-GCM AEAD.

   *  HPKE-2: Integrated Encryption with DHKEM(P-521, HKDF-SHA512) KEM,
      HKDF-SHA512 KDF, and AES-256-GCM AEAD.

   *  HPKE-3: Integrated Encryption with DHKEM(X25519, HKDF-SHA256) KEM,
      HKDF-SHA256 KDF, and AES-128-GCM AEAD.

   *  HPKE-4: Integrated Encryption with DHKEM(X25519, HKDF-SHA256) KEM,
      HKDF-SHA256 KDF, and ChaCha20Poly1305 AEAD.

   *  HPKE-5: Integrated Encryption with DHKEM(X448, HKDF-SHA512) KEM,
      HKDF-SHA512 KDF, and AES-256-GCM AEAD.

   *  HPKE-6: Integrated Encryption with DHKEM(X448, HKDF-SHA512) KEM,
      HKDF-SHA512 KDF, and ChaCha20Poly1305 AEAD.

   *  HPKE-7: Integrated Encryption with DHKEM(P-256, HKDF-SHA256) KEM,
      HKDF-SHA256 KDF, and AES-256-GCM AEAD.

   *  HPKE-0: Key Encryption with DHKEM(P-256, HKDF-SHA256) KEM, HKDF-
      SHA256 KDF, and AES-128-GCM AEAD.

   *  HPKE-1: Key Encryption with DHKEM(P-384, HKDF-SHA384) KEM, HKDF-
      SHA384 KDF, and AES-256-GCM AEAD.

   *  HPKE-2: Key Encryption with DHKEM(P-521, HKDF-SHA512) KEM, HKDF-
      SHA512 KDF, and AES-256-GCM AEAD.

   *  HPKE-3: Key Encryption with DHKEM(X25519, HKDF-SHA256) KEM, HKDF-
      SHA256 KDF, and AES-128-GCM AEAD.

   *  HPKE-4: Key Encryption with DHKEM(X25519, HKDF-SHA256) KEM, HKDF-
      SHA256 KDF, and ChaCha20Poly1305 AEAD.

   *  HPKE-5: Key Encryption with DHKEM(X448, HKDF-SHA512) KEM, HKDF-
      SHA512 KDF, and AES-256-GCM AEAD.

   *  HPKE-6: Key Encryption with DHKEM(X448, HKDF-SHA512) KEM, HKDF-
      SHA512 KDF, and ChaCha20Poly1305 AEAD.




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   *  HPKE-7: Key Encryption with DHKEM(P-256, HKDF-SHA256) KEM, HKDF-
      SHA256 KDF, and AES-256-GCM AEAD.

   As the list indicates, the ciphersuite labels have been abbreviated
   at least to some extent to strike a balance between readability and
   length.

   The ciphersuite list above is a minimal starting point.  Additional
   ciphersuites can be registered into the already existing registry.
   For example, once post-quantum cryptographic algorithms have been
   standardized it might be beneficial to register ciphersuites for use
   with COSE-HPKE.  Additionally, ciphersuites utilizing the compact
   encoding of the public keys, as defined in [I-D.irtf-cfrg-dnhpke],
   may be standardized for use in constrained environments.

   As a guideline for ciphersuite submissions to the IANA COSE algorithm
   registry, the designated experts must only register combinations of
   (KEM, KDF, AEAD) triple that constitute valid combinations for use
   with HPKE, the KDF used should (if possible) match one internally
   used by the KEM, and components should not be mixed between global
   and national standards.

4.1.  COSE_Keys for COSE-HPKE Ciphersuites

   The COSE-HPKE algorithm uniquely determines the KEM for which a
   COSE_Key is used.  The following mapping table shows the valid
   combinations of the KEM used, COSE_Key type, and its curve/key
   subtype.  This holds for COSE algorithms using either of the COSE
   HPKE modes (Integrated Encryption and Key Encryption).

   +---------------------+--------------+
   | HPKE KEM id         | COSE_Key     |
   |                     | kty | crv    |
   +---------------------+-----+--------+
   | 0x0010, 0x0013      | EC2 | P-256  |
   | 0x0011, 0x0014      | EC2 | P-384  |
   | 0x0012, 0x0015      | EC2 | P-521  |
   | 0x0020              | OKP | X25519 |
   | 0x0021              | OKP | X448   |
   +---------------------+-----+--------+

       Figure 1: COSE_Key Types and Curves for COSE-HPKE Ciphersuites

5.  Examples

   This section provides a set of examples that show the HPKE Integrated
   Encryption Mode and the HPKE Key Encryption Mode, and illustrates the
   use of key representations for HPKE KEM.



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5.1.  COSE HPKE Integrated Encryption Mode

   This example assumes that a sender wants to communicate an encrypted
   payload to a single recipient, named "bob".

   An example of the HPKE Integrated Encryption Mode is shown in
   Figure 3.  Line breaks and comments have been inserted for better
   readability.

   This example uses the following:

   *  Suite: HPKE-0 (P-256 / HKDF-SHA256 / AES-128-GCM)

   *  Plaintext: "This is the content."

   *  External AAD: empty

   *  External Info: empty

   *  Recipient kid: "bob"

   The ciphertext (hex) transmitted to "bob" is:

   d08344a1011823a20443626f622358410457229bdd99407b384a9e59fa15
   53224d58b106e9ebebdaa06d2126bd96757674847669966ecb0dcdf21af5
   623f19f0b799b0cddf3ee930b739dd474f6282de0158253f3c1595e9d252
   e816215a9ce73f47ba4b57acb06ecc39ca5a03a14108bbe7807af5688d61

                  Figure 2: Hex-Encoding of COSE_Encrypt0

   COSE_Encrypt0 pretty-printed:

   16([
     h'A1011823',
     {
       4: 'bob',
       -4: h'0457229BDD99407B384A9E59FA1553224D58B106E9EBEBDA
       A06D2126BD96757674847669966ECB0DCDF21AF5623F19F0B799B0
       CDDF3EE930B739DD474F6282DE01'
     },
     h'3F3C1595E9D252E816215A9CE73F47BA4B57ACB06ECC39CA5A03A1
     4108BBE7807AF5688D61'
     ])

                  Figure 3: COSE_Encrypt0 Example for HPKE

   The following COSE Key was used in this example:




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  {
    1 /kty/: 2,
    2 /kid/: h'626f62',
    3 /alg/: 35 /HPKE-0  (P-256 + HKDF-SHA256 + AES-128-GCM)/,
   -1 /crv/: 1 /P-256/,
   -2 /x/:
    h'02a8e3315f96bc7355dbf85740c6d8e53fb070cd8ba5c419be49a91d789ef55c',
   -3 /y/:
    h'96b6621abf5ca532e042dc5c346c1ef0c9186b83cb122e50a46f1458de023d35',
   -4 /d/:
    h'eca39300147c91a2a65d17e00ea278b57a14178245bf5686d9a404cca1816b8e'
  }

                            Figure 4: COSE Key

5.2.  COSE HPKE Key Encryption Mode

   An example of key encryption using the COSE_Encrypt structure using
   HPKE is shown in below.  Line breaks and comments have been inserted
   for better readability.

   This example uses the following input parameters:

   *  Content encryption algorithm: AES-128-GCM

   *  plaintext: "This is the content."

   *  kid:"bob"

   *  alg: HPKE-0-KE (assumed 46) - Key Encryption, DHKEM(P-256, HKDF-
      SHA256), KDF: HKDF-SHA256, AEAD: AES-128-GCM

   *  external aad and info are empty

   The following COSE Key is used:

   a701020243626f6203182e2001215820d832916778598ea6203af974c97b
   45970ac0266fc6a3b7f213ba9f8b591b92972258208d9410599a8e83d00e
   b46d67b34d4dac8fbd4b8b1f08864599659cee9ef09184235820b1162c56
   8efcba91c8e4e82f66e36b45aa10bc55228cf65ecd3bb29cfb09f989

   As a pretty-printed version:









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   {
      1 /kty/: 2,
      2 /kid/: h'626f62' /"bob"/,
      3 /alg/: 46 /HPKE-0-KE/,
     -1 /crv/: 1 /P-256/,
     -2 /x/:
        h'd832916778598ea6203af974c97b45970ac0266fc6a3b7f213ba9
   f8b591b9297',
     -3 /y/:
       h'8d9410599a8e83d00eb46d67b34d4dac8fbd4b8b1f08864599659c
   ee9ef09184',
     -4 /d/:
       h'b1162c568efcba91c8e4e82f66e36b45aa10bc55228cf65ecd3bb2
   9cfb09f989'
   }

   As a result, the following COSE_Encrypt payload is produced:

   d8608443a10101a1055089115f10ecc1c7fd834442cb87929bc15825534d
   b92f5366e3cadd096774a9576bb8d8867e75ea38c329ecfc7b8793c5a4ae
   9603e5b0b6818349a201182e0443626f62a12358410417cd85837981ddb1
   4963061ab5fb7308988eb922f87cf6cf6ef83556f7657922c9815947e41b
   9bc932e48c6f1c4677d9a5506a30d694587628b5193a4cde2f3f58204b50
   8a340e463c317f4e62fb8d08c887cac4788087ad022562d05855a50ca4a0

   Pretty-printed, this hex-sequence has the following content:

96([
  h'A10101',
  {5: h'89115F10ECC1C7FD834442CB87929BC1'}, h'534DB92F5366E3CADD096774A9576BB8D8867E75EA38C329ECFC7B87
  93C5A4AE9603E5B0B6',
  [
    [
    h'A201182E0443626F62',
    {-4: h'0417CD85837981DDB14963061AB5FB7308988EB922F87CF6C
    F6EF83556F7657922C9815947E41B9BC932E48C6F1C4677D9A5506A3
    0D694587628B5193A4CDE2F3F'}, h'4B508A340E463C317F4E62FB8D08C887CAC4788087AD022562D058
    55A50CA4A0']]
  ])

5.3.  Key Representation

   Examples of private and public KEM key representation are shown
   below.

5.3.1.  Public Key for HPKE-0





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   {
       / kty = 'EC2' /
       1: 2,
       / kid = '01' /
       2: h'3031',
       / alg = HPKE-0 (Assumed: 35) /
       3: 35,
       / crv = 'P-256' /
       -1: 1,
       / x /
       -2: h'65eda5a12577c2bae829437fe338701a10aaa375
             e1bb5b5de108de439c08551d',
       / y /
       -3: h'1e52ed75701163f7f9e40ddf9f341b3dc9ba860af
             7e0ca7ca7e9eecd0084d19c'
   }

           Figure 5: Public Key Representation Example for HPKE-0

5.3.2.  Private Key for HPKE-0

   {
       / kty = 'EC2' /
       1: 2,
       / kid = '01' /
       2: h'3031',
       / alg = HPKE-0 (Assumed: 35) /
       3: 35,
       / key_ops = ['derive_bits'] /
       4: [8],
       / crv = 'P-256' /
       -1: 1,
       / x /
       -2: h'bac5b11cad8f99f9c72b05cf4b9e26d244dc189f7
             45228255a219a86d6a09eff',
       / y /
       -3: h'20138bf82dc1b6d562be0fa54ab7804a3a64b6d72
             ccfed6b6fb6ed28bbfc117e',
       / d /
       -4: h'57c92077664146e876760c9520d054aa93c3afb04
             e306705db6090308507b4d3',
   }

          Figure 6: Private Key Representation Example for HPKE-0

5.3.3.  KEM Public Key for HPKE-4





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   {
       / kty = 'OKP' /
       1: 1,
       / kid = '11' /
       2: h'3131',
       / alg = HPKE-4 (Assumed: 42) /
       3: 42,
       / crv = 'X25519' /
       -1: 4,
       / x /
       -2: h'cb7c09ab7b973c77a808ee05b9bbd373b55c06eaa
             9bd4ad2bd4e9931b1c34c22',
   }

           Figure 7: Public Key Representation Example for HPKE-4

6.  Security Considerations

   This specification is based on HPKE and the security considerations
   of [I-D.ietf-hpke-hpke] are therefore applicable also to this
   specification.

   Both HPKE and HPKE COSE assume that the sender possesses the
   recipient's public key.  Therefore, some form of public key
   distribution mechanism is assumed to exist, but this is outside the
   scope of this document.

   HPKE relies on a source of randomness to be available on the device.
   Additionally, with the two layer structure the CEK is randomly
   generated and it MUST be ensured that the guidelines in [RFC8937] for
   random number generation are followed.

   HPKE in Base mode does not offer authentication as part of the HPKE
   KEM.  In this case COSE constructs like COSE_Sign, COSE_Sign1,
   COSE_Mac, or COSE_Mac0 can be used to add authentication.

   If COSE_Encrypt or COSE_Encrypt0 is used with a detached ciphertext
   then the subsequently applied integrity protection via COSE_Sign,
   COSE_Sign1, COSE_Mac, or COSE_Mac0 does not cover this detached
   ciphertext.  Implementers MUST ensure that the detached ciphertext
   also experiences integrity protection.  This is, for example, the
   case when an AEAD cipher is used to produce the detached ciphertext
   but may not be guaranteed by non-AEAD ciphers.

7.  IANA Considerations

   This document requests IANA to add new values to the 'COSE
   Algorithms' and to the 'COSE Header Parameters' registries.



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7.1.  COSE Algorithms Registry

7.1.1.  HPKE-0

   *  Name: HPKE-0

   *  Value: TBD1 (Assumed: 35)

   *  Description: COSE HPKE Integrated Encryption using DHKEM(P-256,
      HKDF-SHA256) KEM, HKDF-SHA256 KDF, and AES-128-GCM AEAD.

   *  Capabilities: [kty]

   *  Change Controller: IESG

   *  Reference: [[TBD: This RFC]]

   *  Recommended: Yes

7.1.2.  HPKE-1

   *  Name: HPKE-1

   *  Value: TBD3 (Assumed: 37)

   *  Description: COSE HPKE Integrated Encryption using DHKEM(P-384,
      HKDF-SHA384) KEM, HKDF-SHA384 KDF, and AES-256-GCM AEAD.

   *  Capabilities: [kty]

   *  Change Controller: IESG

   *  Reference: [[TBD: This RFC]]

   *  Recommended: Yes

7.1.3.  HPKE-2

   *  Name: HPKE-2

   *  Value: TBD5 (Assumed: 39)

   *  Description: COSE HPKE Integrated Encryption using DHKEM(P-521,
      HKDF-SHA512) KEM, HKDF-SHA512 KDF, and AES-256-GCM AEAD.

   *  Capabilities: [kty]

   *  Change Controller: IESG



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   *  Reference: [[TBD: This RFC]]

   *  Recommended: Yes

7.1.4.  HPKE-3

   *  Name: HPKE-3

   *  Value: TBD7 (Assumed: 41)

   *  Description: COSE HPKE Integrated Encryption using DHKEM(X25519,
      HKDF-SHA256) KEM, HKDF-SHA256 KDF, and AES-128-GCM AEAD.

   *  Capabilities: [kty]

   *  Change Controller: IESG

   *  Reference: [[TBD: This RFC]]

   *  Recommended: Yes

7.1.5.  HPKE-4

   *  Name: HPKE-4

   *  Value: TBD8 (Assumed: 42)

   *  Description: COSE HPKE Integrated Encryption using DHKEM(X25519,
      HKDF-SHA256) KEM, HKDF-SHA256 KDF, and ChaCha20Poly1305 AEAD.

   *  Capabilities: [kty]

   *  Change Controller: IESG

   *  Reference: [[TBD: This RFC]]

   *  Recommended: Yes

7.1.6.  HPKE-5

   *  Name: HPKE-5

   *  Value: TBD9 (Assumed: 43)

   *  Description: COSE HPKE Integrated Encryption using DHKEM(X448,
      HKDF-SHA512) KEM, HKDF-SHA512 KDF, and AES-256-GCM AEAD.

   *  Capabilities: [kty]



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   *  Change Controller: IESG

   *  Reference: [[TBD: This RFC]]

   *  Recommended: Yes

7.1.7.  HPKE-6

   *  Name: HPKE-6

   *  Value: TBD10 (Assumed: 44)

   *  Description: COSE HPKE Integrated Encryption using DHKEM(X448,
      HKDF-SHA512) KEM, HKDF-SHA512 KDF, and ChaCha20Poly1305 AEAD.

   *  Capabilities: [kty]

   *  Change Controller: IESG

   *  Reference: [[TBD: This RFC]]

   *  Recommended: Yes

7.1.8.  HPKE-7

   *  Name: HPKE-7

   *  Value: TBD13 (Assumed: 45)

   *  Description: COSE HPKE Integrated Encryption using DHKEM(P-256,
      HKDF-SHA256) KEM, HKDF-SHA256 KDF, and AES-256-GCM AEAD.

   *  Capabilities: [kty]

   *  Change Controller: IESG

   *  Reference: [[TBD: This RFC]]

   *  Recommended: Yes

7.1.9.  HPKE-0-KE

   *  Name: HPKE-0-KE

   *  Value: TBD14 (Assumed: 46)

   *  Description: COSE HPKE Key Encryption using DHKEM(P-256, HKDF-
      SHA256) KEM, HKDF-SHA256 KDF, and AES-128-GCM AEAD.



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   *  Capabilities: [kty]

   *  Change Controller: IESG

   *  Reference: [[TBD: This RFC]]

   *  Recommended: Yes

7.1.10.  HPKE-1-KE

   *  Name: HPKE-1-KE

   *  Value: TBD15 (Assumed: 47)

   *  Description: COSE HPKE Key Encryption using DHKEM(P-384, HKDF-
      SHA384) KEM, HKDF-SHA384 KDF, and AES-256-GCM AEAD.

   *  Capabilities: [kty]

   *  Change Controller: IESG

   *  Reference: [[TBD: This RFC]]

   *  Recommended: Yes

7.1.11.  HPKE-2-KE

   *  Name: HPKE-2-KE

   *  Value: TBD16 (Assumed: 48)

   *  Description: COSE HPKE Key Encryption using DHKEM(P-521, HKDF-
      SHA512) KEM, HKDF-SHA512 KDF, and AES-256-GCM AEAD.

   *  Capabilities: [kty]

   *  Change Controller: IESG

   *  Reference: [[TBD: This RFC]]

   *  Recommended: Yes

7.1.12.  HPKE-3-KE

   *  Name: HPKE-3-KE

   *  Value: TBD17 (Assumed: 49)




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   *  Description: COSE HPKE Key Encryption using DHKEM(X25519, HKDF-
      SHA256) KEM, HKDF-SHA256 KDF, and AES-128-GCM AEAD.

   *  Capabilities: [kty]

   *  Change Controller: IESG

   *  Reference: [[TBD: This RFC]]

   *  Recommended: Yes

7.1.13.  HPKE-4-KE

   *  Name: HPKE-4-KE

   *  Value: TBD18 (Assumed: 50)

   *  Description: COSE HPKE Key Encryption using DHKEM(X25519, HKDF-
      SHA256) KEM, HKDF-SHA256 KDF, and ChaCha20Poly1305 AEAD.

   *  Capabilities: [kty]

   *  Change Controller: IESG

   *  Reference: [[TBD: This RFC]]

   *  Recommended: Yes

7.1.14.  HPKE-5-KE

   *  Name: HPKE-5-KE

   *  Value: TBD19 (Assumed: 51)

   *  Description: COSE HPKE Key Encryption using DHKEM(X448, HKDF-
      SHA512) KEM, HKDF-SHA512 KDF, and AES-256-GCM AEAD.

   *  Capabilities: [kty]

   *  Change Controller: IESG

   *  Reference: [[TBD: This RFC]]

   *  Recommended: Yes







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7.1.15.  HPKE-6-KE

   *  Name: HPKE-6-KE

   *  Value: TBD20 (Assumed: 52)

   *  Description: COSE HPKE Key Encryption using DHKEM(X448, HKDF-
      SHA512) KEM, HKDF-SHA512 KDF, and ChaCha20Poly1305 AEAD.

   *  Capabilities: [kty]

   *  Change Controller: IESG

   *  Reference: [[TBD: This RFC]]

   *  Recommended: Yes

7.1.16.  HPKE-7-KE

   *  Name: HPKE-7-KE

   *  Value: TBD21 (Assumed: 53)

   *  Description: COSE HPKE Key Encryption using DHKEM(P-256, HKDF-
      SHA256) KEM, HKDF-SHA256 KDF, and AES-256-GCM AEAD.

   *  Capabilities: [kty]

   *  Change Controller: IESG

   *  Reference: [[TBD: This RFC]]

   *  Recommended: Yes

7.2.  COSE Header Parameters

7.2.1.  ek Header Parameter

   *  Name: ek

   *  Label: TBD11 (Assumed: -4)

   *  Value type: bstr

   *  Value Registry: N/A

   *  Description: HPKE encapsulated key




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   *  Reference: [[TBD: This RFC]]

7.2.2.  psk_id Header Parameter

   *  Name: psk_id

   *  Label: TBD12 (Assumed: -5)

   *  Value type: bstr

   *  Value Registry: N/A

   *  Description: A key identifier (kid) for the pre-shared key as
      defined in Section 5.1.2 of [I-D.ietf-hpke-hpke]

   *  Reference: [[TBD: This RFC]]

8.  References

8.1.  Normative References

   [I-D.ietf-hpke-hpke]
              Barnes, R., Bhargavan, K., Lipp, B., and C. A. Wood,
              "Hybrid Public Key Encryption", Work in Progress,
              Internet-Draft, draft-ietf-hpke-hpke-02, 4 November 2025,
              <https://datatracker.ietf.org/doc/html/draft-ietf-hpke-
              hpke-02>.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/rfc/rfc2119>.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/rfc/rfc8174>.

   [RFC8949]  Bormann, C. and P. Hoffman, "Concise Binary Object
              Representation (CBOR)", STD 94, RFC 8949,
              DOI 10.17487/RFC8949, December 2020,
              <https://www.rfc-editor.org/rfc/rfc8949>.

   [RFC9052]  Schaad, J., "CBOR Object Signing and Encryption (COSE):
              Structures and Process", STD 96, RFC 9052,
              DOI 10.17487/RFC9052, August 2022,
              <https://www.rfc-editor.org/rfc/rfc9052>.





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   [RFC9053]  Schaad, J., "CBOR Object Signing and Encryption (COSE):
              Initial Algorithms", RFC 9053, DOI 10.17487/RFC9053,
              August 2022, <https://www.rfc-editor.org/rfc/rfc9053>.

8.2.  Informative References

   [HPKE-IANA]
              IANA, "Hybrid Public Key Encryption (HPKE) IANA Registry",
              October 2023,
              <https://www.iana.org/assignments/hpke/hpke.xhtml>.

   [I-D.ietf-lamps-cms-cek-hkdf-sha256]
              Housley, R., "Encryption Key Derivation in the
              Cryptographic Message Syntax (CMS) using HKDF with SHA-
              256", Work in Progress, Internet-Draft, draft-ietf-lamps-
              cms-cek-hkdf-sha256-05, 19 September 2024,
              <https://datatracker.ietf.org/doc/html/draft-ietf-lamps-
              cms-cek-hkdf-sha256-05>.

   [I-D.irtf-cfrg-dnhpke]
              Harkins, D., "Deterministic Nonce-less Hybrid Public Key
              Encryption", Work in Progress, Internet-Draft, draft-irtf-
              cfrg-dnhpke-07, 16 October 2025,
              <https://datatracker.ietf.org/doc/html/draft-irtf-cfrg-
              dnhpke-07>.

   [RFC8937]  Cremers, C., Garratt, L., Smyshlyaev, S., Sullivan, N.,
              and C. Wood, "Randomness Improvements for Security
              Protocols", RFC 8937, DOI 10.17487/RFC8937, October 2020,
              <https://www.rfc-editor.org/rfc/rfc8937>.

   [RFC9864]  Jones, M.B. and O. Steele, "Fully-Specified Algorithms for
              JSON Object Signing and Encryption (JOSE) and CBOR Object
              Signing and Encryption (COSE)", RFC 9864,
              DOI 10.17487/RFC9864, October 2025,
              <https://www.rfc-editor.org/rfc/rfc9864>.

Appendix A.  Contributors

   We would like to thank the following individuals for their
   contributions to the design of embedding the HPKE output into the
   COSE structure following a long and lively mailing list discussion:

   *  Richard Barnes

   *  Ilari Liusvaara





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   Finally, we would like to thank Russ Housley and Brendan Moran for
   their contributions to the draft as co-authors of initial versions.

Appendix B.  Acknowledgements

   We would like to thank John Mattsson, Mike Prorock, Michael
   Richardson, Thomas Fossati, and Göran Selander for their
   contributions to the specification.

Appendix C.  Testvectors

   The testvectors use the following input:

   *  Plaintext: "hpke test payload"

   *  AAD: "external-aad"

   *  Info: "external-info"

   *  HPKE AAD: "external-hpke-aad"

   AAD is the COSE Enc_structure.external_aad.  It is used as AAD for
   the COSE AEAD in Encrypt0/Encrypt (Layer 0).  HPKE AAD is the HPKE
   AAD for CEK wrap/unwrap in Key Encryption (Layer 1).  It is only
   passed to the HPKE Seal/Open of the CEK.

   =============== NOTE: '\' line wrapping per RFC 8792 ================


   HPKE-0-KE COSE_Key:: \
   a70102024d626f622d68706b655f305f6b6503182e200121582064ea61f745f7deed\
   186d697a4c89715932755017766348b0443a60aac450b5a622582088f53a4cbbcfcc\
   1bf0b33d5dc60f789a7f495244f57c158a8ceed5179639152b235820e8de39325f3c\
                    0be02442076c470a46bca742de9bc2be453ec1dc049dda1f6ca3


   HPKE-0-KE with default aad, default info, default hpke aad

   Ciphertext: \
   d8608443a10101a105507af5398f1827c014f68bdb9fe84152eb5821d25b7b5eb83d\
   c30f3a4d9ddadd9bd2726e88c621182d88ff53b39c5688c558f732818353a201182e\
   044d626f622d68706b655f305f6b65a1235841040189cdaf807a039007db9e298471\
   7cff68554f1bbe372d73a7af89cad1b3b1ecdcfca75e2c3786ac3a7f61bf303395e2\
   768b114ded2f4be39d40fff7917bb987582011a6de6b6c1e5240a1035c1239c7a8b3\
                                        000e7dc383818a97099f19b6c2b73b1b


   HPKE-0-KE with default aad, default info, external hpke aad



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   Ciphertext: \
   d8608443a10101a10550d68d7921fc2bf04d033edc091c7045f2582167788960ecb8\
   6bc44a71b67d4fffabaa94c032e7b7f639cd28574b9080b817e324818353a201182e\
   044d626f622d68706b655f305f6b65a123584104c73249f22b8c4171fecb3bd1093d\
   3c6a1288aab904db50cb7c688a5dcb02ef22fc734d6091472016fe087bd0eaa71694\
   821314321c6d193d842c220c7f58d819582075ea467d773d97db62deb5fd1507607e\
                                        e7ca47e467cedcd79f16a4072678713a


   HPKE-0-KE with external aad, default info, default hpke aad

   Ciphertext: \
   d8608443a10101a105506a6c63e17b739c728d65b66d39e85174582118b37ca471a5\
   306ba4745b9578e6a8cf618bc01d7f4f9f16c28049dcb12027677d818353a201182e\
   044d626f622d68706b655f305f6b65a1235841048115885e297b224f955c5ee9344c\
   944801e8633e9305763125bd0739656f6f0495af6bccb2c1e34d06ae586b186bdb61\
   8913e718456be702c2c84196ffee06245820e62641de898fa0534bfbaa671949554f\
                                        6d9db266270b0cdd8b53ff4255353a1b


   HPKE-0-KE with external aad, default info, external hpke aad

   Ciphertext: \
   d8608443a10101a10550f07d00afe300fe71beb752cadca5bb245821beed09dcab8c\
   16c6ac26ddf5df3d47c6638467cb231ba934882499db30a5073d7b818353a201182e\
   044d626f622d68706b655f305f6b65a123584104b1d54393905a8551df3a675032b5\
   97ce40fa18dee7a4b11fe0ca93524e4f20cd6de652360acc99e72f8b620039d33a9a\
   1bdd542158a1a16b6d152264ddb701f95820602d1e4fac1cd619fd5f54bd625dd186\
                                        1d80ddf6f4e220922616a05cc86018cc


   HPKE-0-KE with default aad, external info, default hpke aad

   Ciphertext: \
   d8608443a10101a1055089035dbd98078aac856737fc9ce06eba58210c356b57b017\
   0d371bf2cfc4c5d648164036726f33498ff2c99b1cee42257a197a818353a201182e\
   044d626f622d68706b655f305f6b65a1235841047ef0f70acf119a83c24b967af181\
   514fae47996bd0eafb4d8641e967802f28d58940fcfb4d28b4df4745a30700036b3b\
   ccc2ced18c1375865f421e583fb0a77958202f93933dd09fb3db2cd287b738664d34\
                                        bc263c89fab8aa6d46fa1d431814cd5f


   HPKE-0-KE with default aad, external info, external hpke aad

   Ciphertext: \
   d8608443a10101a10550edb91df2666a50b438779cbcd25ab4b158212b48ca390e8e\
   5903e467390347a8f4da0710ae6c66d90693083d8d62265b72fd5a818353a201182e\
   044d626f622d68706b655f305f6b65a1235841041fb11d2984ca125db16fd99fd8c3\



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   f64862daee939a212fc68ddd275ee75b5c25a4b71c73d9620951d9897410c2a9f2f1\
   9aa5932446ac9b36b0ae1e913fe7bcc458200eec5d2195d413e32a60b593008a85a0\
                                        cc1ae74c63823feadd35eca3aba3786b


   HPKE-0-KE with external aad, external info, default hpke aad

   Ciphertext: \
   d8608443a10101a105509ab67637694ffe1f4420ededf9a3e4ed582110b9cfa11046\
   c75524433a693b8bcafea8522939afa042519495e46e1c40996869818353a201182e\
   044d626f622d68706b655f305f6b65a123584104ae1c16e230410ce4f385288a7d83\
   ebd0d12fa6760362e98c2c42dde16f8caaea74971025d8b39bae72a127fd795068d7\
   f3447a282d37295609e9b60dfa1a672958207ddfc787b9372d6ec0215a8504765947\
                                        271074e6e81c48e2c6d5de95ac306526


   HPKE-0-KE with external aad, external info, external hpke aad

   Ciphertext: \
   d8608443a10101a1055012c4d08a6cb6da8dff2c072a152858875821064264f2652b\
   166a88373bd9cedd96d38cb65c650726578910ae6e6e6313258f94818353a201182e\
   044d626f622d68706b655f305f6b65a1235841043bf1b7f2d106d364416c27f3d7cc\
   d03c3d803b9bd473c521456c51f8c1a37b917584b861c100c42eb0eb048519bc10d6\
   75ac8013174e669af6bed0f814cb614e58205c9e7e8f86b7ef1ba9f94425c9b0d8a7\
                                        f43fc56df49da6b414629c2b7c96f489


   HPKE-1-KE COSE_Key:: \
   a70102024d626f622d68706b655f315f6b6503182f200221583003fcd256d1fd79ce\
   8d6d29e3cb72a823380e1c655aa2ce211721245873bacb76eacd6e28f4557fed2552\
   46a76fdd61b82258304dd4aa71088792b44e00970c2f269c1eb546e848a6df2946e4\
   409777deb6d7b77803a383c9e87757cef9f18910a1f76423583035172a2ccec0f1d1\
   af547b811754e01de5406257ca808f2fabcbca5cbf7a4d22b951fc1d4da0e89e8608\
                                                            fde30d2f6706


   HPKE-1-KE with default aad, default info, default hpke aad

   Ciphertext: \
   d8608443a10103a1055820aac05a4dcbdd92e82befd10b4724ef077579404dd106c4\
   bc33c69cb549cac1ed58214597a425b09b4ab5f169143378a5ff92169be65260098c\
   5ae834659444d753f672818353a201182f044d626f622d68706b655f315f6b65a123\
   586104bc7ed2fa3f73a546de2bae35fee30c39cad00e7883f85f2670a9eceb547262\
   dfb8f676f701b7143a6ff693380b397c23572dd677fc7bd6a5de005662ef9f8a3c33\
   5c81b69b59fa585a70e449ae581421ead6f7a0a6d9c05e9fdcac0db1f60605583008\
   e7f0466569e452d0f3e45aa99aa9dddeb04de6398fd55100578046c27e15ba13fd2c\
                                              abc5a33202ecd547a4c7b0c99e




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   HPKE-1-KE with default aad, default info, external hpke aad

   Ciphertext: \
   d8608443a10103a1055820c8ee79fb915867c74d950d05f6ca9d43d47f714936684c\
   a7f0254d7df92ba68f5821e74e07295b12fc4a8e518c5cff4d05df0bcfe55d29804c\
   6eaf2a176ddec72249f4818353a201182f044d626f622d68706b655f315f6b65a123\
   58610463a670ebf1628d5a6238c131aa98bee619c1d007aa703e3312eff22c2145a9\
   1f0dcb1e4787082e81720649780786e409fb9be9b7589d9d78e1d735cf1c664d4721\
   4bc1d4dfd06216c07a8ada1b3fe0f41fb759965d65755dd59e74247561b19a583021\
   15a5dcd6d165a7b30736723a4da24df149a89c0decde47e554abfc995b55a3eb89dd\
                                              52d5059b96449ccd243fd93665


   HPKE-1-KE with external aad, default info, default hpke aad

   Ciphertext: \
   d8608443a10103a1055820ac71a5659fe597a604fcc77a3d5b2b52bcd0d7d00fc5e1\
   57caf21ea9666a1f685821052f34eacd31e88626a199ac533fd0308b74268a3cd320\
   df3e8697e5cc9ec6d211818353a201182f044d626f622d68706b655f315f6b65a123\
   586104639aaa2fe678c4186e9578c16dc72d6006ca8f7df7946b67843d7c4248da84\
   d6a8ebb0f58fb84689c54b1f23c8390b41e77d4bc4c93159ebc3a7810316ce505544\
   ac2d81309fb45eb64a3401558921e37cd861aeaf895e9606b066be1a609bea5830bb\
   266370fdb5c56669e4c88c86329ea9a84dde052c9482e4c6b305945d7c27e081b1d7\
                                              cd5cd39c65ad4a4bd4bbeee875


   HPKE-1-KE with external aad, default info, external hpke aad

   Ciphertext: \
   d8608443a10103a1055820172e4e1b4df69bb472d261bfb43c78433c330625eae7f4\
   a4e31cf10b2ceeb94d5821ebfa1a3352ed030fc5fef08ae1c1066bc7d9108fd45def\
   05396a6b4cd3401af48d818353a201182f044d626f622d68706b655f315f6b65a123\
   586104a355c7e5fa4a166ff68825bf094e81b9744aa2518ce381721c329952f26bbd\
   de60f5fbde96fa47258684bd7277e545d3320b367ca06f42a56f6cf0afaaf1cb8ea9\
   6e4fa46b9db1dca72fd19988d9af9234d2b02a251eee800fcc03c260fa23205830d5\
   f92ee2d4eff9323732c0fa70a071fa068c1572188b67ce1401657ff32c1cf4d3bcb7\
                                              0d2144ba4cfc323e4f93d8b8bf


   HPKE-1-KE with default aad, external info, default hpke aad

   Ciphertext: \
   d8608443a10103a1055820393f4c0886145f63d4de2012757a496b46f80da705c4fc\
   7f045618b2b1bbe74d5821a580ae1f89bd1b84e546d94628c97c3548118e74c5026e\
   ec543442b0bdf92f1d01818353a201182f044d626f622d68706b655f315f6b65a123\
   58610483ad6cd4932f0fc73a7e0640b5db583082b0d741b64a948404adc5624e67e9\
   167e9d81fd8d98e47afc006c2a366ff8f1c4062565c8b1e9a2cfe791120addfa86ef\
   6b444e957982a3f194fa2e932f6987b8ebf674b8a96d5ebdde8a4edcd1fefd583088\



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   f136f57fa98c10df0b8a09d1ed6833a25e197ee653652f104265e20acf723bb2ff7d\
                                              aefc9db56f2120186c1d991978


   HPKE-1-KE with default aad, external info, external hpke aad

   Ciphertext: \
   d8608443a10103a105582086dbfa77caffcdcbc96b45ba891dd2b61a88ad0940ce5f\
   dadf44526eb3b043ac5821a558899a7bc196b4b252f5cbf13a6d1ab2b45a083719ae\
   0bcd3ac3cf16a45f911a818353a201182f044d626f622d68706b655f315f6b65a123\
   5861045cd0a1afae98177f0f2fc52d75eb0acc5b4b8464ef7f14e8b0d90410f88449\
   6f21747e0b589b1fba09b0da8312476cfa7492e4dff1258128b9be4cf6d8e94e9725\
   75935075767d186029a34d19115d4fd908565389ecfd21a4a528eeecb1a704583095\
   8ff6ee18bd7aca20198ba18b220658c1db5c67a2251600c1eb698fd85812c271a5ec\
                                              61be430a8c985c9d0922815e3a


   HPKE-1-KE with external aad, external info, default hpke aad

   Ciphertext: \
   d8608443a10103a1055820d19b7e6c324f92b83ee77477d5a646cd88b986b8c6f83c\
   dec36c7d4892f7ba7958212d06813db517713f343ff5125ef2ac14c41b574b931cce\
   50bd48b4ed3e2c5dc8e8818353a201182f044d626f622d68706b655f315f6b65a123\
   58610499890247ae97c42ff00408e71396e17ff114ac35f35849da6452c1cab3cc78\
   186a65bfbf7a7c79e12c78f7c562af7ab5c06ac4066f175c49d5992efab2c521c5d2\
   90549caee7d175e32d3f9bf1212b438c61eb8a010ea5956ff51d207d197fbb583064\
   b27d50df0f0305c139c7545bb339b4341c099d40294b55fe31ffd10d53ea9c6a58ad\
                                              a98a89b5b7a2419434df7e6f16


   HPKE-1-KE with external aad, external info, external hpke aad

   Ciphertext: \
   d8608443a10103a10558209f03b841a61b17bf41e3afb0109933abc9750cf9a5f6d6\
   90a96283c9a8b30cf05821613a6eda5df30ef01a9d5974dd0f28598f587803a0e644\
   cf22f5b78e42f38a9259818353a201182f044d626f622d68706b655f315f6b65a123\
   586104f85e706f0b1469fcc2bad6a25cb801418954d78344bf56e855e4d0241dc654\
   d4050e224480e99644949875243cdb0cce4ab352e6e9ff3106fec195fa4bebe994da\
   650208b34b55b2f6a433609d6343d43e5a8abe8db28dc06f665cdef59984a15830a8\
   17dd751be11ed8596225bed31887383299ee632cbe319443a2b6f3bab515884c423e\
                                              0af2a29e7db0ee13daad9d69f8


   HPKE-2-KE COSE_Key:: \
   a70102024d626f622d68706b655f325f6b6503183020032158420033db899e500ac6\
   f1fb7a9e23f16a363e41b6d1f6dd5562c4faaa0491f1a74cbdbd039ff2b5824842d4\
   da26c36173bc31ba2d1672699d871fdca27b9af0020bb580225842012ecb4d569869\
   085618ce0a4e0f82fe9b618dae8b678e26e7a1ed8d8b9bdf7ffcd32dfdee1bd85ee5\



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   2097866c4f493a3174e6abb6b365057d212ce3d84a5010a6df235842019f28872f68\
   9d9c3a8018712e453a23beac37cb86c87e2c5a99d7e3901f2e4f4995fae274ca0774\
                    8a7076d0ecae6466a7c3cdbc55d233544a59d22d3e4dde1d4b5f


   HPKE-2-KE with default aad, default info, default hpke aad

   Ciphertext: \
   d8608443a10103a105582036694bc81347438c501dc55add947708ba52ce8bb52aa7\
   b2878d26a0b9878d855821e6032422deb9c62db49d50c0011197c39b586660b7a018\
   443f1ab285f707019f69818353a2011830044d626f622d68706b655f325f6b65a123\
   58850400d55b883bb4f6f54cb0f147826fb706f01ccb19d67a8df4ce4bdf451f39ae\
   2c4e77370558c529c2022dd39e07f36e315705cafe57249ac9abd1fe0fd821a366bc\
   e6013a2b390c1d3bf50f47cf19df06ee0564716dbc589c325a46fb66526167710a82\
   a4e40c55629fb48619dde005fa002b994b240ab481c37aa4170f7d38c61674eee958\
   30933543fd556de228367ef1d4b1b6407461bd4a7acede97d25ebf67590078cc3fe4\
                                          9408300ed29d23be1c27b2902317a8


   HPKE-2-KE with default aad, default info, external hpke aad

   Ciphertext: \
   d8608443a10103a10558201d84edbb7cdff030f465bfce04a1e69e888bb092d660fc\
   7837754591aef06e4158218fdcf224296ba502062f6029071f5f120ce2f8f3ba20e8\
   1052a9e34dbda21026ec818353a2011830044d626f622d68706b655f325f6b65a123\
   58850400c2d331ea52e37a71ca3b32abf85f25ef92ac398c806de067fa344a97b111\
   f00677a62ed2eac2d540e5685279ec03ee69a6b23ed78baf8229b7aa83d76318d86b\
   7a0142ad7baf09f065fafa8c887a5151272fd219d9c0b7caebf4f4e1532e261b5df4\
   e5ce1b6ccb5dbfd86f5a6d7f0c34eb7f2da17b89831ebbf56791d18fb305c0197f58\
   3076cf3e4a3ff03606752d6b7e09806c02aa35a4677452bfd0dbd1a8abb9de682978\
                                          a6d0ae2be5685d4ca48c85b5b2c0e4


   HPKE-2-KE with external aad, default info, default hpke aad

   Ciphertext: \
   d8608443a10103a1055820ef1d313af4d977ec69da4dec5fb387920fb5f0e1843dab\
   998a24ee94aa47a119582186a225225aadeed9ed918e6d1f48c4697e10a07085aa6f\
   cbc0fdff18189b85f361818353a2011830044d626f622d68706b655f325f6b65a123\
   588504004074fd0f72b7237966abf252c0e41a21c5566e0f8c94c2a86c6d21e16035\
   c57a887e5f69a3adf44a1580992bac716f2693a8fd3771043b022d016771b0498569\
   390168f4cd133158b2da000169f8676e3499161f35be790f7c26bd984b339b00ce50\
   5c18b3470f0e159741d63a1fe106eb1ecb6ca50c8130670f28c97bfc625ff33eaf58\
   30935ea79f6e36fd6785bcdbcdcfc737f01400d1262aadf8f2814a123cbd5a498550\
                                          f3f30978aad8c71b5dec58238e9d61


   HPKE-2-KE with external aad, default info, external hpke aad



Tschofenig, et al.      Expires 3 September 2026               [Page 33]

Internet-Draft                  COSE HPKE                     March 2026


   Ciphertext: \
   d8608443a10103a105582050ffa1a4eddc067fa06db21366dc53f4746d1d7b4f9fdb\
   9e02532c80591e621258217c27fb226998f944de516cd7a13509aed1070e72bd4639\
   f955efe6626a202ec97f818353a2011830044d626f622d68706b655f325f6b65a123\
   588504004a73a294d7a1c96685a9ca89dd657afddb2fd8263474d5d020d46a59ed66\
   290770b6e7989c60f800eeef64de8f823c9e40c99b5deee652b5c5d450b9ea127dc0\
   06009e49e147db35cae26ab891572765c4fc588962d0f71c046c3f7f627f09a41e9e\
   682d0d1740720ee8b73adb777c44fdcf4c343b08aaf01849c32ae4cdaa56e04a8958\
   30609a822ab35ac0e183c1049d0e80556d443c8a6f80a27da55f8c34605c240b720d\
                                          beafe4961fd95eac09dafa4c090de0


   HPKE-2-KE with default aad, external info, default hpke aad

   Ciphertext: \
   d8608443a10103a10558208abd74a6f6494dca72c2dbdbd5f7771a508fb43adf7772\
   08e7dc828a9ccf024d582133db1cbe20bb05829a6f1a2d4bdad78d4b3c9e10dd9d3d\
   e106454fbd6b967361ee818353a2011830044d626f622d68706b655f325f6b65a123\
   588504012af1fa72a02b73aa86229266d417f82dc19c55ff550f122e354dc3c7866a\
   ef669f26cf2b57f9b9d3f373903dd1d0ef0c5189d41aa7cbfd4bfc4c955e5727420b\
   980076484702ecfbf448298ffa72d1d31f36d9dfd629104e5bd5f226c6fb992fa754\
   51d0114144b1908e93a3d5c5db83064bf973c9ae2f7876b669a55e49a3dc9bab2158\
   3040424efb8c1c3827fe491bc7e426dff929402372dcb44e5b29103ab7254204367d\
                                          72f56df75003b07fe4294b93fdc2a6


   HPKE-2-KE with default aad, external info, external hpke aad

   Ciphertext: \
   d8608443a10103a10558203099a01f838a003fc9119ee15835749011e099d23026f1\
   34a96b0ec2a99711005821aa17b650a15695339c627f95080f37b0e27bdd56d75863\
   6cedf5ffa1028490f407818353a2011830044d626f622d68706b655f325f6b65a123\
   588504015b3422b8aa732b57dba50e817eacef848ac0f6f9d41fe2496512442044cf\
   5cea24778deff337c76b26fe23f7f3820d95e22766d72e2ddfc54750c6c1089b585e\
   250043c612eeaf05c49b1df18066f8b4925d287c3b36b6177206b8964bcb9d2aab62\
   c77117444ccb4164c7e60e07df0a00ccd28f19747c3d1b4999055a215e06dd0efc58\
   3046501065f28c600ff9872eadec2c958d4435edbf3c6aef7fe8b01b6b7fe625e53e\
                                          0186a9d52b26573031b49009ae1808


   HPKE-2-KE with external aad, external info, default hpke aad

   Ciphertext: \
   d8608443a10103a1055820d6571aef69ca1d95c29f8e32138f3b4cf73d6de02bd42f\
   21c5c245dd1281e95d5821aaeb110acefa649d60730cdf59fdfbfe99d4cd468f0af7\
   9912a996d6fc62946107818353a2011830044d626f622d68706b655f325f6b65a123\
   58850401a18bb1ccfe76360447ac01c17cfef513f41ab8a9d621aac0c3f1cd523fc1\
   5748ba0aa4526745260f918826fac568c9c1788db3ef20cabcb60d057ec4d01f7146\



Tschofenig, et al.      Expires 3 September 2026               [Page 34]

Internet-Draft                  COSE HPKE                     March 2026


   cd005e52a1743fce60440f6a7e630165bee4bd7059ea01781488bf397416920d33f5\
   5f1cf0d01c89a90611c5a5a07cf493d693b02266d743a972652ca94e8652fa52ef58\
   3011f8320f59b91a8aee140d2edf61e0da9db310e42759577c3254f927b7d83d85d2\
                                          632a955ab4e1bb2c5093b37a8ea138


   HPKE-2-KE with external aad, external info, external hpke aad

   Ciphertext: \
   d8608443a10103a1055820ebd94a697400c2eb88607a0bc538915e63f5fdbe4f528a\
   11e559244b773da7115821af4eb2942d7596739651bb60b4de3c456cf74296af3cf0\
   665de158cfaabba1b188818353a2011830044d626f622d68706b655f325f6b65a123\
   58850401db35d812f17987c11a82fcc40bb40c540a7ace9c35b4da9b65dc03ef67e2\
   199b066a3ce082f9da9f596b73daf89b643756f8e29df45d0b78b002ba1d96f2661b\
   78005472f944fd1172c93c04df2e8a6452ddf5ba4c932d17604b58591903de3f60c2\
   8557a781269ce31779c1f2d752ec1fe9fc6ffdcdb6f21a71e6ae5969d07fffc0fe58\
   30d96f3bf5629c8c9cf315cac23cdf75c72c013df31434f9999eb2852111faa0d3c3\
                                          6c5e7f1b5ebd81b0644c38ee8e3bec


   HPKE-3-KE COSE_Key:: \
   a60101024d626f622d68706b655f335f6b6503183120042158202d925acfd0ee359a\
   68565b619165985a7108f7b1771131e26f11d24177dc9a3c23582060cb9ff63744ac\
                      dac02a48527dfc2810fc49bc1223a240d870fa2d668c891155


   HPKE-3-KE with default aad, default info, default hpke aad

   Ciphertext: \
   d8608443a10101a1055057c9f2b6225deca6982d8f501953628a582168e4b863ae09\
   e0179dfe7368d92c0e998ba891791004ac55f05b81fca899dcb975818353a2011831\
   044d626f622d68706b655f335f6b65a123582071075e8a1b304ef9edbc2936f6e5be\
   4ac2e4e7ad59ad37d748fb580bb5fc5c5858205b3704e4c7fd8f05c51fde7f159e70\
                                      1aeba21c55b82dec0e42b9bf9a6a9634c4


   HPKE-3-KE with default aad, default info, external hpke aad

   Ciphertext: \
   d8608443a10101a10550320b164a39702b84ad08f8e9b741445658210a1cda2aa5fa\
   b6fde7026ef7fbef3faab763d7e3ef2b06aa09ca08b4de09a15d84818353a2011831\
   044d626f622d68706b655f335f6b65a12358209e0d94bb2d354bd6a83b9374d9984b\
   e125bde4ae96230eff1d10d0254e96a97d5820b3aee0a1d634043403d61ba332ddf8\
                                      fa899430e0221ba127eec76399a026a359


   HPKE-3-KE with external aad, default info, default hpke aad




Tschofenig, et al.      Expires 3 September 2026               [Page 35]

Internet-Draft                  COSE HPKE                     March 2026


   Ciphertext: \
   d8608443a10101a105508c0eca59bd53bffe5ef3b539c4ea5d6b5821e60895c561cf\
   c588bbd124dbdab7bd2a19590f93e712f6bb3f745c6c8912366ce2818353a2011831\
   044d626f622d68706b655f335f6b65a1235820a141613c5ce54168fc1b9d76a4a28b\
   6461c8b65a14220086c3da2704ca0406695820bdd73f84ffb4d11d4d92391dbb34fa\
                                      8db2ee4f81299203f529f98ce52e49de86


   HPKE-3-KE with external aad, default info, external hpke aad

   Ciphertext: \
   d8608443a10101a105502ff672957f5586fd4a08d0fb045c6639582122758f93e861\
   925e3e40dab68a550046043c0b6183690696116b93093888e52ed1818353a2011831\
   044d626f622d68706b655f335f6b65a1235820a95c290e4366159abd514194334177\
   5f58521efc1ab15015bd368f10bbd5a53f5820c540b2af48b165f272a72d3a133846\
                                      d6915627cbf3a37db34a312cd86cb5a9f7


   HPKE-3-KE with default aad, external info, default hpke aad

   Ciphertext: \
   d8608443a10101a105503a42e93d02472760b51fb62b464b4b9a5821ac8e71b022b2\
   4b2288579ef0c1c854afd28b74e9e784fa5d2f1528c477a0c90740818353a2011831\
   044d626f622d68706b655f335f6b65a12358203c9268ad53ea237b648a1806d667a4\
   5f74dcb725c7777fc558d4566cdeaadf605820dd50847d57ba2906c45b3365153bf9\
                                      3cad6dc9dc049fca46d91ac07a5354c069


   HPKE-3-KE with default aad, external info, external hpke aad

   Ciphertext: \
   d8608443a10101a10550dc32f24a9fcb7dd8da12372b7ccdf3505821ad11bf317640\
   a6c1051ac0453ef9994a9a8a21dc34f2bb8ad17ac17bd902dc420c818353a2011831\
   044d626f622d68706b655f335f6b65a1235820bbca5f776f840f0c4eb5f1994c9989\
   2fd595f9df6e45787550a1624d3a3468255820140a9c10b359b476982d18f7f0fe38\
                                      63845501a020fc311b8a8a513df115acd6


   HPKE-3-KE with external aad, external info, default hpke aad

   Ciphertext: \
   d8608443a10101a10550b224ec850a723d60cd6fade231f03a7058210e151c37f85b\
   ff7b382fd4158339d10bc1746a7d26dccf21d37e122f45456641a0818353a2011831\
   044d626f622d68706b655f335f6b65a123582056e5dc366ead34698fc0b4071a7406\
   c6910beb1e8292b3dd9436ae34b653a0055820edd2498d3dae8e148360ea18f07d59\
                                      e0adb4d283519d9d4b3820c9148f5bcd5f





Tschofenig, et al.      Expires 3 September 2026               [Page 36]

Internet-Draft                  COSE HPKE                     March 2026


   HPKE-3-KE with external aad, external info, external hpke aad

   Ciphertext: \
   d8608443a10101a1055062670829c5fc6f5cdc48faab828dc09e58211ed421e07f98\
   eca98f1155790c790e6710a53484310a47f3b7afdbc77b5a7cb5a4818353a2011831\
   044d626f622d68706b655f335f6b65a12358204370a8614e9d71a82998498493fedb\
   d974def1ba2f3ff34feb5c8bbb1898484c58201e284bb8a5f35206429c5326036316\
                                      a4c4dcd5772b7ed9dffdd1e3cfe02ad9fb


   HPKE-4-KE COSE_Key:: \
   a60101024d626f622d68706b655f345f6b650318322004215820a5922a701eebdf66\
   5a7877e32b0651db5d3ad8eb4be792f2dfd9d9ac5d04956123582000f28ee18a4ddc\
                      dd4f318dd88ba71efe0bb68002015e9c4879e99edf4e9c4b60


   HPKE-4-KE with default aad, default info, default hpke aad

   Ciphertext: \
   d8608444a1011818a1054c06361aad32854c99401d9613582107f6ed7364a443fab2\
   dc1710de081e8e535d621ab98d45e92cd15ecfac213dff6d818353a2011832044d62\
   6f622d68706b655f345f6b65a1235820ba1cbbf9ccacde066147b54ea4c28806c41a\
   dd5495c37295d520d5332d247102583022d9d848d1e3603de56c4a3a0ece5ca75e6a\
            51b929d28142a53067f6169001da5320bbe23facb5c4f6f428f35c4af1cb


   HPKE-4-KE with default aad, default info, external hpke aad

   Ciphertext: \
   d8608444a1011818a1054c9c4cbe7dc327ce468d50bd9e58216f145b2851c502d5b0\
   c3ce4bcd99e96299e2aba606e2af70338c91b31c68a7613b818353a2011832044d62\
   6f622d68706b655f345f6b65a1235820e1e167e1917be9aa3090108e145a03d0fd20\
   4242800da4cab096573fb5f4f164583071397ad12d2a974dd23eaa363f40d3c59c6e\
            706b6b4c8d2a4ec4a6de92e860c30552336591bec0a8e51fe293bca83740


   HPKE-4-KE with external aad, default info, default hpke aad

   Ciphertext: \
   d8608444a1011818a1054c3d211831f229feb2b70db089582105a0acb03ea75dd18d\
   53bf05e648260c91c890355985a11d527eb8c4189590b08d818353a2011832044d62\
   6f622d68706b655f345f6b65a1235820c18fb4814d1f116b82836aeb213bd3528ae6\
   a2417da08cc5abb6b15575217b345830ec408b0789d9097e9be5101e9e84a3076089\
            55570547964d2d840aecef45909361477ce85b012d4ad0d3bd9b2fad9101


   HPKE-4-KE with external aad, default info, external hpke aad




Tschofenig, et al.      Expires 3 September 2026               [Page 37]

Internet-Draft                  COSE HPKE                     March 2026


   Ciphertext: \
   d8608444a1011818a1054ca3a0a911408279f90ca90b0858214cbe2773a824c0e526\
   c75dfd20285b2cef1d39605ff9b64e4f3e16ba943e237263818353a2011832044d62\
   6f622d68706b655f345f6b65a1235820e2d8f154d1a40c518058770f0f345b9d448b\
   418397ccc42d2af887ae9c137210583016932c4f4a574d2ab03dc02729dbaf404330\
            a21df11e1ebc2e52c462e48fed0a0cd3219bff3e9eef5fdc19d92aad161c


   HPKE-4-KE with default aad, external info, default hpke aad

   Ciphertext: \
   d8608444a1011818a1054cd7ab613f6cc110a022aaba5958210a1b3f842a6c339bc9\
   39bea0ec5a0f265777f67d8bb4b826252b6252ba4cdfc6db818353a2011832044d62\
   6f622d68706b655f345f6b65a1235820f8fec4f5ada1c6f6a6b1ee9b89092200c8a4\
   81daccfb51fd47b4fa99709427465830cd5b8342f3727d7afa5b981c7be6edeaada7\
            28833f801ec658cc77763d6de36af71122a250c5edf7df853c54dc486fe9


   HPKE-4-KE with default aad, external info, external hpke aad

   Ciphertext: \
   d8608444a1011818a1054cff6ec38f45005c1d36229a2858212291e110fe7cca10f0\
   258abfa31dbb9c8d019f88dc297f7a1641474650db40ec82818353a2011832044d62\
   6f622d68706b655f345f6b65a1235820e6fec434687bc3b5cd0597c4a56d76c325fb\
   8c21d4dfe8e7aaa47b4572c58f4a5830167720e484a884f32f961544bc2fa865cbbe\
            e622c73bc98424871e7dcc9e7dbeb8b50edc8f6bd499a0e08b9bdb916841


   HPKE-4-KE with external aad, external info, default hpke aad

   Ciphertext: \
   d8608444a1011818a1054cbde082e4f5995e02d5ecfa6d582116efe45e6ac45104ad\
   f41a3d46a627ad743f8178a0a326ddc1431d030172bcd35e818353a2011832044d62\
   6f622d68706b655f345f6b65a1235820a7252d0db32722de877846fefc59ceadd29e\
   698db423ebe3577cd6c0af195f675830520b088ea067725bfeb093abd31bb7516423\
            3a499171855f3d68cd93cad466d56fc29119c475b10e29a69951163383a1


   HPKE-4-KE with external aad, external info, external hpke aad

   Ciphertext: \
   d8608444a1011818a1054c2bf44cdd95f7de613426342c58210fee2d9d95bf69355f\
   f885451849a0dad422dcb3cac652e11413bb87a16da8c333818353a2011832044d62\
   6f622d68706b655f345f6b65a123582063915e953e2d4a681251ae4e19fb61d4d059\
   1cb6cba32d989ec97d0d9c65841a5830c8fc0abec5ee853241c63be826b682119856\
            d9dcc511a0aa4ae5121555afe61980716cd793312fa52ca130649e8b69f9





Tschofenig, et al.      Expires 3 September 2026               [Page 38]

Internet-Draft                  COSE HPKE                     March 2026


   HPKE-5-KE COSE_Key:: \
   a60101024d626f622d68706b655f355f6b6503183320052158384489c1479ccd3534\
   3a90b3e1cb4922f73d9d611f12bf4abe9f76fcac6a6a974c0941fa602dfc29fb5c52\
   b3191ea896162718d2ddbc97097e235838785cb877d73f034edaaa14d66dc3e10bc2\
   8d3ee5a290310c89eab7e347a82218874963600cf36850a389325fcbb6e4477dcc0f\
                                                              1b65e860d9


   HPKE-5-KE with default aad, default info, default hpke aad

   Ciphertext: \
   d8608443a10103a10558204ff93b1cf652bd6b3a78aa66aff3cf0763c4607fec098d\
   0ca74a6036f299ebb2582146d06eb19d65874a09970bcd52bca5d1ae70aef68302b9\
   5771ca57914b3100bcd4818353a2011833044d626f622d68706b655f355f6b65a123\
   58384099e311ea6ecb8c1bb579b3192634863e32c15374551b7cd76f38278cb25065\
   4fc7bd8d5d10d3bf020f5338fc89cb27b1be472ef2687617583092b0973eecebaefc\
   480ad5e606d6def1e78d22ee546831e49df7b91382b5d34e41e9262303525bbbe921\
                                                            afce1d3b4c25


   HPKE-5-KE with default aad, default info, external hpke aad

   Ciphertext: \
   d8608443a10103a1055820ee0407489df27075ea6c15d2c798ea0610e969b18d3d30\
   1867abfc60d14c571f582102485c143d33f60e3e3e6bf52e24a317991ef505085bee\
   6b593d85bfd763dc7593818353a2011833044d626f622d68706b655f355f6b65a123\
   58381e027e0f01b9ce80513f2945e81582922f593186a4ba6f015bea962a5856e321\
   00552f29a141e7ea288f379a2a3e6a6204ee5cbc37970c955830082a8b17e3e65548\
   20c31107b8b50d97caca42f6fde213a4c7494257d019e7d3bb00410301d3113d8114\
                                                            6f64b1d649f7


   HPKE-5-KE with external aad, default info, default hpke aad

   Ciphertext: \
   d8608443a10103a1055820add0563a9487a69fd84c520c1b403ca469bfd31b3888a7\
   badf1ace338489cc9e5821e5f53fb6e1baeb79c1e42bc88e414d25bb0deecb3fb75b\
   5e5ccc71a5c514b1b33c818353a2011833044d626f622d68706b655f355f6b65a123\
   5838a1cb8855ddead0ae82b4e87df4b399b7197b2f06d5ba0f4b053b104b760db9e9\
   b2d53d924d403bb243cc2fa51d9d0eabf20150db69ad419b583014330834835b5951\
   ee83fd58ebea9bb375ec5df0b373eec65c15a1f59ae7fddc8d16eaf11f67d98dcf4a\
                                                            b833b21e2669


   HPKE-5-KE with external aad, default info, external hpke aad

   Ciphertext: \
   d8608443a10103a10558204427ccf295f6163509a646b90fd9c40ed7a0fe9384cb10\



Tschofenig, et al.      Expires 3 September 2026               [Page 39]

Internet-Draft                  COSE HPKE                     March 2026


   36a17b813b237524f2582103723c06533e16224e98d151063d708c7dc4c09b53b872\
   346c6083adee8b2fb43f818353a2011833044d626f622d68706b655f355f6b65a123\
   5838d6b7013b4c9f9b44ea55d9edaec03be7591cda435670066f3878c89ea5d49005\
   f683d0dc1a8c85dddd9a79c8ff5993876b25dbc5e1231b275830ddafd2a0712a6845\
   f11970adaf619f844eff75c8a381f80533c393fc5dc114b83a902c672af3d5390a4e\
                                                            478ec6897ede


   HPKE-5-KE with default aad, external info, default hpke aad

   Ciphertext: \
   d8608443a10103a10558208919fd6f31b0cbbdda4875af585af67e0c0823cef6d0be\
   cd6802ea3ecef0c9a55821fb88175fd00fdda16def7f4110899c4f9017c63ec4b375\
   73f0dc4a97b6d9527b22818353a2011833044d626f622d68706b655f355f6b65a123\
   5838203f42bbdb8cfeb59f7c05a1580a885554f5ef8848c76a04a011b2b9521f08a4\
   bf7d159b8f01762ab304ff57637400acc22d62746a942ffa5830ad7cb3c1c79711a1\
   1aff71f09a29228341485376d569fae65673c5a0ba0a4dbd5b7904ad2cea0ce1aa2d\
                                                            af37adc25e73


   HPKE-5-KE with default aad, external info, external hpke aad

   Ciphertext: \
   d8608443a10103a105582085aa9e38bdbf1f258426becc819a929c55e719cc75227b\
   a515ae09a8267bf4925821f5d3bd70c82cdcd96595efbc671919c2698af5ef96667a\
   b16894f6dd7ec5dc6a95818353a2011833044d626f622d68706b655f355f6b65a123\
   58384d97b5bc0f662d782b9122f113ca655d156674d3381b45f61a55f6f670771bba\
   eff2187824469740f49ed0ec5bcebcf991851bd41fa95d5858306e0bd0c92cd5e4f6\
   c74a34319a4738051e96cc3ddb69b6ef8dc0710918d02940c10688cd828b303b4b35\
                                                            95d8bf2c0056


   HPKE-5-KE with external aad, external info, default hpke aad

   Ciphertext: \
   d8608443a10103a10558201806b9f94e356ed2f2c10b0822ff35b1504dba0b5a1db8\
   af9b8e0d5c3792068058210a5eabd5d60b81eeff382c7598898e4fca0efcad5b27b3\
   cdc05ae412b771495d4f818353a2011833044d626f622d68706b655f355f6b65a123\
   5838e3fbd237c85215a1d247176714e27f198a0f7a76e83f5116c97b218b5204c300\
   06dd08abf94892a44bf00a358f67822d3bf92d331b6430ba58307fd5803d162ea9ea\
   adb8fc37b327d6b4a526a07ce4a13697195579ba6d7230f444568d1b731443f3bf6f\
                                                            f5d4f2c4e375


   HPKE-5-KE with external aad, external info, external hpke aad

   Ciphertext: \
   d8608443a10103a1055820de43c2aa8af6fcaf531231f6403cee6800fe1e3d0fc614\



Tschofenig, et al.      Expires 3 September 2026               [Page 40]

Internet-Draft                  COSE HPKE                     March 2026


   7e090c1595fe8467ae5821f29e9f566935b3ef34e043891c935094dc1fe4984dd30a\
   ac5877f98b0759055303818353a2011833044d626f622d68706b655f355f6b65a123\
   583803884f02e4d336a193959844a73db0b95f2511121886dc7bf82b945f8337c025\
   56efa96811b63cba029b13c60e9581a38366d6366177db4e5830eb8e0f189adaaf28\
   7119963680320da63ee1dc219982e7145cbef6437472b977344bdf141ceac4c4521b\
                                                            cd971c154ee1


   HPKE-6-KE COSE_Key:: \
   a60101024d626f622d68706b655f365f6b650318342005215838253b435291775cff\
   909b2227b8bd6f539f521368b33871022f95713b4433df21becfffeaba9d63e839e4\
   3413e92689ead254feae3d7aa8e72358382c6894f63ec5d05047370d9415d4c0cd53\
   ee2633926596788a41b5ff5368733b7d9499c391b08ed7c1c3d750c4c5af2ff03a44\
                                                              278c7c40b6


   HPKE-6-KE with default aad, default info, default hpke aad

   Ciphertext: \
   d8608444a1011818a1054cdc91705d85a0564634c28b9458210a72029b5ce3c44b85\
   28862f5f5764e438c7d723cd412bf65f681f7382b2084ecc818353a2011834044d62\
   6f622d68706b655f365f6b65a1235838e2d1ffe83d043f7fde6f14658e6ea3827e57\
   8bd060def6491ada7311a260c4b3f0734b97d3c3b8cd50c6f667df518c3d6a9d60c1\
   d2563e8058300dc6bf0ce7314032e954f5eac21d5646b3d8a0f50a1beb3414da3e60\
                                333d15b9edc7b8f9615bbb411b053268968b0be3


   HPKE-6-KE with default aad, default info, external hpke aad

   Ciphertext: \
   d8608444a1011818a1054c161f8d0c535147d452345f7b582105686a0762c213b2ab\
   775b71f5752e91a14ea742afc9be7d4dcef77408cbb3b474818353a2011834044d62\
   6f622d68706b655f365f6b65a1235838a06b9b5d98702887a49304d2cd174da29014\
   08c3a012cbc97c8548afd5e113a8fbbafa02df731f4f9ec314aacb389766defccbe5\
   087da31d5830395054dceb31dbac2381c37bf04f1db0f79b184482fba8f92a7ce31c\
                                b4fae7ebd9c4f52a1730ca3cb76695af047ff6cc


   HPKE-6-KE with external aad, default info, default hpke aad

   Ciphertext: \
   d8608444a1011818a1054c2eaa13b8a25bf8e0971fbaaa5821abe79da1ef9aa997ec\
   00bcfbad70283b1c82874557c74f6d411742f0f35534c232818353a2011834044d62\
   6f622d68706b655f365f6b65a1235838c88eb6e1e4a8901cdda6340b0f6f0a22aef1\
   eb93b8c9b0396e0390e4e11ceace150773c38614076b4a65890cfd87376117e92925\
   80ce9ba55830a1fc1274c68b001884bcc2c0bacfcd1c16ae3bd12366edf28da11adc\
                                ede0a5ba7b02550ac305f74e0c2e6993eb980617




Tschofenig, et al.      Expires 3 September 2026               [Page 41]

Internet-Draft                  COSE HPKE                     March 2026


   HPKE-6-KE with external aad, default info, external hpke aad

   Ciphertext: \
   d8608444a1011818a1054c777589e4029d40667c3f5113582178d2b8e3a9b4b7a676\
   0a5d442476370bb171134189415ce45957c2325ad5e6e8fa818353a2011834044d62\
   6f622d68706b655f365f6b65a123583805ab0e5f240b5a0add796adcf658a865eac3\
   b661b19b45ec84d19d87eb4ce789f11e51a6641907d71a79a7e9e00372f8b03185a0\
   aaafc23158303e0e1cf5cbe04cd7c99c804ab120374f4a53aa31cf867cdc6222e1c3\
                                3329e271e2b10723e09c3e58e0d5440ff1674877


   HPKE-6-KE with default aad, external info, default hpke aad

   Ciphertext: \
   d8608444a1011818a1054c79c3898eee0f5d0c139ea9d1582122c443c0fb066dddd0\
   05678ab35d2409e37145f3a2c660212b307c567107d481e8818353a2011834044d62\
   6f622d68706b655f365f6b65a1235838c0d3df69fd572cc5b4ea701c50d3251b9aa2\
   8620a0885b9377b2287c52ac6a25381921c735c82f0d471ccf8eff4f7096336db9d7\
   6231c8fd5830152b3a5f3833c4aed2d9d5a8e15b782543dc84709ac4706379eee3e5\
                                e334b0b9f56aec8770765c7b26bde266af673208


   HPKE-6-KE with default aad, external info, external hpke aad

   Ciphertext: \
   d8608444a1011818a1054c342275d497bd01b56282649c58219cedf5c89b5f3e1bca\
   d64725c0d90a2184eedd1e8b7138b80d8c0f5cc1abf89e33818353a2011834044d62\
   6f622d68706b655f365f6b65a12358386e741c2825336f78c666cc7ad296920b25c1\
   1b6d482b235ad243172ce301dcbcaee23a076beabc6c282f2ba757d50fec9c6af0d0\
   706d98275830e89f61c2fbdafb5573cfd12220dbd4545fa54b4d1412833db1b56ab4\
                                84f486164138d9b84a2b16bdba3c7993ed8bd4a6


   HPKE-6-KE with external aad, external info, default hpke aad

   Ciphertext: \
   d8608444a1011818a1054ca9fa34a4e5f1846e9afeb0a258219e4b6d9512d4d4fde5\
   c5ca94d3babd478132a1ba3f92448fd25dcd26a483c2cb25818353a2011834044d62\
   6f622d68706b655f365f6b65a1235838a23c08691c61200eb23cf535ba0f0252f7f0\
   09f9ce24f7df7ad71a974536a01ff52d2ba12345d74bf751fd5382166aed53b2a786\
   35d4aa7d5830691f2d587f1748e87ba11dc1c10dd7602712789e85eaf63990d36a00\
                                5ceb9041c119c8629d0cb366a8aafe0473a56b4f


   HPKE-6-KE with external aad, external info, external hpke aad

   Ciphertext: \
   d8608444a1011818a1054c226a8d618d7ce2f1a116e7a8582120c2989b87f908e508\



Tschofenig, et al.      Expires 3 September 2026               [Page 42]

Internet-Draft                  COSE HPKE                     March 2026


   443d80c3c7d35c3860da0fdf77edd51846874e38153d9b43818353a2011834044d62\
   6f622d68706b655f365f6b65a1235838ae833f2ab29229c1fe66f025d30facde2e87\
   71940275f0b67934cad41822a7325ae9669f3cf8dc11c034c9105d67188a40d0343b\
   ce70bcdd58301e78d4468b91719a6f1e6f6a2e98efa55f92a0713984e4fa677f44f3\
                                9acacf65559af142b5216786588123e8fa3d73d8


   HPKE-7-KE COSE_Key:: \
   a70102024d626f622d68706b655f375f6b65031835200121582055137ef3179b4bba\
   4326a5e73ae0966d92d2ccc7e1714a66fba562a1c597a08d2258201daa17ff95d717\
   128dc944069f4060af5981575734f1f847e6bd6bc30603cd6123582073294f0f394f\
                    08becf7358ea89c0cda596cbd9705a6b7c6f0ae8d70a9a85a913


   HPKE-7-KE with default aad, default info, default hpke aad

   Ciphertext: \
   d8608443a10103a1055820b4ad67bdb6937286a5983cc45f54b41e3c7a0df82e12f1\
   b7e7925bde628eca6a582142b48f53df1fcc1caf84bc4820476082e55146a04e1726\
   aabea65114de8329bda5818353a2011835044d626f622d68706b655f375f6b65a123\
   58410433c37c35e3c3c333aff1bc62edfa2765518c7cd4e025a8b23ffb3fcf78f13d\
   051cdb830d89f97e1567f27362420b63d0cbc4c1dcf6df18f2c599e763c575c3f058\
   3029ee7739a3699d79e1ffbb652f99741a1e2d15cc05bf68d8a9f55bf3b77e33c22f\
                                          5c7bdd3a842031325f385f6ed972c4


   HPKE-7-KE with default aad, default info, external hpke aad

   Ciphertext: \
   d8608443a10103a10558208123621364280f31244476af7ba86971aee01f51ec197f\
   63127acc2845c1c23e5821f71f66a19a63bf08eeae9cab07ab5c8454816f7370a6c4\
   f58630647a5988d5b823818353a2011835044d626f622d68706b655f375f6b65a123\
   584104ba669a6cdf24f9eb902c0647fa7011c764d210f10c4de956188b2137829b73\
   6b1d0ec5e6d71ca286d279391a4d129ba3cd904edc3d61ee98cf45528b81e3f9db58\
   30b2e8ad669f478914862185c6ec6f70593d29b8e2ec523b7d89f9cd914ad34ca775\
                                          2fe3629b4680c8466942adf7a14ac2


   HPKE-7-KE with external aad, default info, default hpke aad

   Ciphertext: \
   d8608443a10103a105582073a819dcb519a63355b711e7ba4bd278a25a5065983b94\
   90f0169c3ca1a6c446582159ef651b16dd3eccb599906d27a3f3d06e09efeb0bae14\
   7f5cc3cd8ad876697401818353a2011835044d626f622d68706b655f375f6b65a123\
   5841044fd069ae9dc9a029979615eddba8e946dc4087817c8e02680dce2b0415fa88\
   39904afe73c3c045f32a010603ee158deb96e3c5a97c501fecf9b29b8914d4a71658\
   304c694a5e09eecc922621d3dfe02b7e5dd0ff7c174ad6001f24a0764867f8a3c18d\
                                          ad15a51d85542ef85b0753f4654cee



Tschofenig, et al.      Expires 3 September 2026               [Page 43]

Internet-Draft                  COSE HPKE                     March 2026


   HPKE-7-KE with external aad, default info, external hpke aad

   Ciphertext: \
   d8608443a10103a1055820bd1930d292a90e8c717057f53fa6bf9058e0b9d3e6c013\
   c6e19061ad839a47cd58215bc9e46ef5be53dea520078ae2e41ccd5b9b5419f273b5\
   dd8c35459184eb8a8512818353a2011835044d626f622d68706b655f375f6b65a123\
   58410438bd711f6e6cea92c0008fa4b6e6874d6466ed63ae3031a87ed03d074b236f\
   1b07526363c63f5d90ef5ee45a41e00f726f3bf1c61a0de461f1da41545f055c2558\
   30795f8c1b78115df8af58f49b8f5fd94df744f50f6f36836cd15441dceb88c196d0\
                                          a4014ac8ed81832a6a106dc974591f


   HPKE-7-KE with default aad, external info, default hpke aad

   Ciphertext: \
   d8608443a10103a1055820921ada478a6296b81674ec480e27ff77ef0cc691967b23\
   5920c45be58079f1fb5821bc50d6b7348a33fac2aff9d9b289dce83c8a60050309fb\
   6f432d564a6e6b909366818353a2011835044d626f622d68706b655f375f6b65a123\
   5841046d92481c24059c5d5ae998048868ac975a2d87136c62dd53fca5cce700f45c\
   2c7da093dbf84545880f8f81fd51b9d73622153324ffe35ff80ab9edc828b6db9458\
   30f6c919e08dc6f0dddb0bec457ceb6726f5a3c18d97389d96d894b553e602f0d484\
                                          49740735f900b1d6fd7e4003457ee8


   HPKE-7-KE with default aad, external info, external hpke aad

   Ciphertext: \
   d8608443a10103a105582003a092a86b3432027f1eff4e1cad509aa786f73a5148a1\
   7d0071b7798a5b2206582153bbf01e70aaec7dfddea48b28dd511afadc6edc7524bb\
   e449ac677c2136c994a5818353a2011835044d626f622d68706b655f375f6b65a123\
   58410481bc8c8fd41e43207e76e38a808c04c69ac716e4e95d712732df1bfacaf548\
   039db70e5ec9374f6744eb88b8d4480de1caa03f6fb7a3c9ae7b60f7715e4bada858\
   309d22782eedf0f851fa507b74fd05d1bd7d995e15bbd5162ef0ab08840cda5b6b55\
                                          a7ed79500990cefe94a8f312518bb0


   HPKE-7-KE with external aad, external info, default hpke aad

   Ciphertext: \
   d8608443a10103a10558208e23d1384869e09d81b29aca4a6c914f5b6e1fab762986\
   00146e7b82bcd3349558218784389faa384d51bb2488fa493d63f2e3fe72634c9994\
   4c5a8b7bb32e6ad4b5fa818353a2011835044d626f622d68706b655f375f6b65a123\
   5841041542669339ff82f8c64acb331de9103d339042bf8bd61d75056cd05d70d136\
   c2b481b1dd2b220196228a1f4a8f70991176deb68ca4900a698878900cd3bf763958\
   30f611c9c31785c2d7bcca2638da2375131fe2287b72f4b4b93ba1d8424ba12fe6a4\
                                          8bb8ac5d0bad1cf7b8f81cf9d11bcc





Tschofenig, et al.      Expires 3 September 2026               [Page 44]

Internet-Draft                  COSE HPKE                     March 2026


   HPKE-7-KE with external aad, external info, external hpke aad

   Ciphertext: \
   d8608443a10103a10558200014fd43c613aaa6578d3001abeef3c028cb1c3079f21f\
   f6da777a9c586b985f5821333e109d32d4cb58224e3cc3958b0696233e4a824586fc\
   953056b55fb0f988f9e3818353a2011835044d626f622d68706b655f375f6b65a123\
   584104cfd2686a4ab624d792050d5fefd9f128467196fc437fccc02643ed770b1944\
   502d9515c98bad76e6b4c3c982ea8192124bc3dfd61901af0bd9676e5e189a93a158\
   30334cdf07561053063f668bb025f4d46cbab5202de419d34ce5e49290c886763b17\
                                          0fcc5586f9eec223a6a94ae484542c


   HPKE-0 COSE_Key: \
   a70102024e626f622d68706b655f302d696e7403182320012158206699b067898b7d\
   2d37db0da3aecad4bdac1558870b47d67d080d6049fb81752f225820b01b6da1f210\
   f46e20e2b552a80f4f6b9a3adad34a6701f73fbbeffb174cf7412358206716e93d65\
                  94fbfd27016daada9ccc8e6ba2eea0e103e3d7ae22278f6dfe124a


   HPKE-0 Encrypt0 with default aad and default info

   Ciphertext: \
   d08344a1011823a2044e626f622d68706b655f302d696e7423584104bb6385b1cd50\
   09597006380ba2de0f66d293007755640f57b13a234bbe7241cf6f91f45469f85e99\
   a13b9567257b7025298bcf6e7f4c1f29ab5229381f4b99e65821ed584cb52cb37201\
                      35d1aed21adeca560e00effb931cf17f9b60542abc92e80b63


   HPKE-0 Encrypt0 with external aad and default info

   Ciphertext: \
   d08344a1011823a2044e626f622d68706b655f302d696e74235841040c483c4a0f7e\
   41e98c585fdb19ab95789ec6f7f6fe3e7e4943e3e0ce147e42c0688808a3284f779b\
   d374d2a83e72d0248e3c6339a932cabb35c084071b75670a58218c9fd85ac5f111b2\
                      ef077872bcf72a7222a8ed8bdcf6f4036f304eb03c75450067


   HPKE-0 Encrypt0 with default aad and external info

   Ciphertext: \
   d08344a1011823a2044e626f622d68706b655f302d696e74235841048ab08975a473\
   b7e85a8796479a986b1d57270074ab819bbea2eb48a666c78fd4cfa1558f56dbde81\
   848b19b1a2bf9a8438dcf8e4a2d800bb155cbb6e9b41956e58217a8a794081022469\
                      dab987927fff8e642d7f2f44b96eab7bb5b78b8fe7b5e6f2a5


   HPKE-0 Encrypt0 with external aad and external info




Tschofenig, et al.      Expires 3 September 2026               [Page 45]

Internet-Draft                  COSE HPKE                     March 2026


   Ciphertext: \
   d08344a1011823a2044e626f622d68706b655f302d696e74235841049d1716049cee\
   3aa5f23d2b3bbc96fd251262a97d3b0dbc53eac742b8c89fe887af7ab816ca8aee7a\
   bacacd1a2ab0495e57aeff22611139d1cf894a666529b1615821590565fd461c31ed\
                      bfb529c208c29b87c7c924b9c570d8308cb006f1c86b646544


   HPKE-1 COSE_Key: \
   a70102024e626f622d68706b655f312d696e7403182520022158308309a370b333f9\
   56c1cff9d94e1ef8aacc2808ca898fec0476d9c132893704a2a4ecc88bd002e2c713\
   83b97bb3ab65822258304b2a3e1b2fc832c136aee1632f967b31f5afd0a32c8c9766\
   d0e9d0e4e2560a905278b0d9965898b3fe4d2165cfa1b1c0235830bde0361bbbf278\
   ff3286a36897b2e674286870981ef471c2c81b55a3b82827800d32b34da68993cd59\
                                                          0ff06e0788aeaf


   HPKE-1 Encrypt0 with default aad and default info

   Ciphertext: \
   d08344a1011825a2044e626f622d68706b655f312d696e7423586104652d74d6ded6\
   32be58dfdf81aeb3e7f365f86ad170c509dac27c2107551538c5b4ea89f36b6aa431\
   5b39ec96528c7b0d049f5c70d801e6d522e7a91f559b52eb2b706d93f3f11d1cfbd1\
   906a5c4c3380150d46926c3f469526389ecd0e1f9db6582144c5fd46930ccf302b53\
                          15faa3337d76c8622fe8ec6df824ad7e376007d52e02ac


   HPKE-1 Encrypt0 with external aad and default info

   Ciphertext: \
   d08344a1011825a2044e626f622d68706b655f312d696e7423586104106388d784f2\
   cdaab13c77b6f67d0229d552ce2e7707dc5a17ec01f74637d4275ad2a931ca7d0062\
   f7bf45be096cc29b7b2ba96efc974ce673c29d47a7a2db63eb0a5c55aa6c5abf9f72\
   8f7b4f29435437c59409584a61cbcd4a83a1f876fe1c582174d9cbc04fd6fcc0ad6a\
                          a587a38f21be70e381f4b8de184c4e7e3fffa246418ac6


   HPKE-1 Encrypt0 with default aad and external info

   Ciphertext: \
   d08344a1011825a2044e626f622d68706b655f312d696e7423586104fdd2d7553bc3\
   1201851cacb28ec135df4ba6f4cbc92362a18d3024ba3944a74ff46bad3cedca9721\
   5c8e5c337aee23a04bf42d777fc2a38e14ffb0337a983de8e6fdc28714b527180733\
   33aa374bca263d1b270bb61098be1032271cf5e166fd5821124c3c9acc6700f6faab\
                          0503ea8306ccafa6ad341e69017b5d57877bba7c8d7c4c


   HPKE-1 Encrypt0 with external aad and external info




Tschofenig, et al.      Expires 3 September 2026               [Page 46]

Internet-Draft                  COSE HPKE                     March 2026


   Ciphertext: \
   d08344a1011825a2044e626f622d68706b655f312d696e74235861047a2c8b275dd4\
   8bba7666452c6ee4db7e4d9c53790344b446223753d4fd6c15b6a513cf223af09355\
   62820f9336396edd5a096498dd7c49cd7dab87a86cfa03ef507bdfc3de2403569cf0\
   2bd702afd76c756d9aae114ba4dc5b94ecd29f62d383582171c1a6219cf72d7446a5\
                          9c00c5fa692d17c0efc3b92c34a2ff0cc56adcea9b65e7


   HPKE-2 COSE_Key: \
   a70102024e626f622d68706b655f322d696e740318272003215842003c20a6d2990d\
   ac871dec57d8f31283ca99b9958a00e92ba43b1ff9186813f750b01333ef1f311960\
   1875065599aa48884425480a4d20e8e39bc84e98f745d91ed72258420058edb9dbcc\
   ddc1594dc9003ab39886babd7ef7d0046aa72eae0f9c67b794c251c8a2309ae05f6f\
   1cf4ac06045ecd45bc335d5c316936e3968e6ed42211bfdaa859235842010c50be4e\
   0322d8bcb1424750f6ed3b22bcbe25ae9745a868688dcbbab97f522f5a95d0712b8d\
                  9ff48a5be6650179fd4e59913c76b1b28af9605ddb294756c2effd


   HPKE-2 Encrypt0 with default aad and default info

   Ciphertext: \
   d08344a1011827a2044e626f622d68706b655f322d696e7423588504009a6b229af0\
   1086f3d269bc53e80af50c51fa34d7919137f7ee341773859909eb8a42d528d3cb4a\
   a8d11e2b0456a1eea80b77a5ac960c22899e96bcd5a41b57277101eb8043867d62f6\
   4de2c6400d5239b17d5fc1c1544eba22ee4c2f464fbb88a0b24d532b7587727cca8d\
   93f5a39997a3cb9ef2490ea1d1fe46a45fa96fb2b26bf6ec582199e3fd2ccf2add11\
                      cd4be8ea6819e00af7b3a37d46e674ab6028376ff99125ce2e


   HPKE-2 Encrypt0 with external aad and default info

   Ciphertext: \
   d08344a1011827a2044e626f622d68706b655f322d696e7423588504008f1fbff7e1\
   c3960d04ed74bdd86b19c995af96468008b7ad62e9ca2d060c222fda6bd30831e04f\
   e797b6a87f7b0eb325a2b0b0e5331d302aaf69aa386ec9276fa901dc4056f6331d58\
   093273ed605c1e1e32b2e368afe71390246f8fa20d7ffc6e790a06d86e588f658bb0\
   bee30c523101b351433ea1c611cd0d2fdf6e924fce55eed2582120bb19765d3444e4\
                      3325d1c8a7d4a510c4a85a88cf3b9a2763e477f9e064e08510


   HPKE-2 Encrypt0 with default aad and external info

   Ciphertext: \
   d08344a1011827a2044e626f622d68706b655f322d696e7423588504006dba8c9caa\
   d42c743aebca073875e1e5780c828162072850df9a8c83975f64dc4466152a8bbd12\
   d7bef79c00a589a0b8bced83b8fa82fbc1a50a33e0a54a1420ae010b5dd6dcc9bd0b\
   af5101485f37d011fdd902dad39843343bb57be244e566047a60d54a15ec9c8d25d9\
   1b97ea7be7a1ae118898ec8c273d88198ba4d0f5e74ec14b58218e160a01123c22b9\



Tschofenig, et al.      Expires 3 September 2026               [Page 47]

Internet-Draft                  COSE HPKE                     March 2026


                      a4f4859a9d101bdad6ce576c6cc68343ec54f32f644facdba2


   HPKE-2 Encrypt0 with external aad and external info

   Ciphertext: \
   d08344a1011827a2044e626f622d68706b655f322d696e74235885040100fffac417\
   f1ddde4c2f9316e7031d73aeb7e21e2223da751c310971d8d78861fe437facaad58c\
   2a72abc8ffd5c9c052ce345c7dd7a871204f8d90669bc8a3679f016ef52865c7bc9a\
   221dc67c1a9c12405943772a7db4658c8855b80b6883812ba92017f8fb98bf9bad12\
   ac14a7e2eaea2c7fb3a9513e117ccf69c3e6998abd0e3e2a5821657d17e9ca01ee51\
                      f7a88a870ac0719e2c1ae8d0881e6e9c03ffb4834d586aa98a


   HPKE-3 COSE_Key: \
   a60101024e626f622d68706b655f332d696e74031829200421582085eb6351a4e93a\
   49953e1e23ade9504af68a73196a823c9a0654bf98c7536a7f235820f0b8ece6e393\
                    8430f36798eeea8206d0ac5e0577349ad63843cbbb63bc90b849


   HPKE-3 Encrypt0 with default aad and default info

   Ciphertext: \
   d08344a1011829a2044e626f622d68706b655f332d696e742358200a97fc27b9542a\
   666479ad6635d9d5988e2bb187db4f8b3b48f60f2d06bac46b5821f058dcbad9bad8\
                    553fd6cbccfd50486e33dd96557d5805c6327af6624760bc7a1b


   HPKE-3 Encrypt0 with external aad and default info

   Ciphertext: \
   d08344a1011829a2044e626f622d68706b655f332d696e7423582093a055592c2978\
   fe4c7424e649938700ead043668b0a12c4233350f7927a250958216ec61f83f6fab2\
                    79d636bbc78bccaf9d06d34b9f39b0d615b26066c1c584fc05e4


   HPKE-3 Encrypt0 with default aad and external info

   Ciphertext: \
   d08344a1011829a2044e626f622d68706b655f332d696e74235820b9a5e203033c7c\
   5d15bce2c35cd59e24db38db2114b9c5d16edc5d7ec4cfb54f5821807a3046ee8c72\
                    5701d5e9bf5472772e84b5a2cffbd4b296d55af264da8b14b87e


   HPKE-3 Encrypt0 with external aad and external info

   Ciphertext: \
   d08344a1011829a2044e626f622d68706b655f332d696e742358201d6124b3462a25\



Tschofenig, et al.      Expires 3 September 2026               [Page 48]

Internet-Draft                  COSE HPKE                     March 2026


   d3ed374b88a4702afa7831aafd81af5c8774eceef569f0234658210fcbc960c3f6a0\
                    49cbff49d881fff00a86152cfbbeccdeec111fdadc848665b9f0


   HPKE-4 COSE_Key: \
   a60101024e626f622d68706b655f342d696e7403182a20042158200191a45e724023\
   3a4bda72ac8b38283aea336c863c7d5856b7df263038bc69072358200838e90c3407\
                    649faf0bd7eeb3e5a9fd7c643e4cb72b91997fc81d26d2f1de49


   HPKE-4 Encrypt0 with default aad and default info

   Ciphertext: \
   d08344a101182aa2044e626f622d68706b655f342d696e7423582081cbeefeef0b8a\
   8b736f700fe52ff25f0cfc7302e5075a44b95e7cf5a82a96775821e5c0ebf3de1016\
                    b0fd33f41c0774d6b283dd494537c729ad7decab64bd5c1f43e5


   HPKE-4 Encrypt0 with external aad and default info

   Ciphertext: \
   d08344a101182aa2044e626f622d68706b655f342d696e742358204c41250100e5f5\
   05dd0acf8830ff1d22e7954d8f6d88d59c809c95d903849c4658218c99cbbe71f8f6\
                    95e6e79dc6f412793c3ea9d1464066e2d08aaa27b5fef24ec144


   HPKE-4 Encrypt0 with default aad and external info

   Ciphertext: \
   d08344a101182aa2044e626f622d68706b655f342d696e7423582004aa6884ce80e1\
   88a0ef5496c24f6798afde8c8dc623bc2654ce836bb2b9be4158211bc91f4db16f81\
                    fdab012e74c00ae5353eb258e433b8ea4b28893d7436fe7615f2


   HPKE-4 Encrypt0 with external aad and external info

   Ciphertext: \
   d08344a101182aa2044e626f622d68706b655f342d696e74235820bcf1e847f43e3f\
   4244751ce5e4ac782fc5270310590a3cf8fb825e5ad6be54145821e9c1313608956f\
                    65a12558a94ce3fa04ec84ecdeb2eed4eee2a4fbbe783cfcfdd7


   HPKE-5 COSE_Key: \
   a60101024e626f622d68706b655f352d696e7403182b2005215838fa09d4a5d1fa3a\
   7b2b6de43b08c715283d7425b80bf8b628b07d0d077283aa9c1507354e98c087688e\
   8cfe7220be5e2d44509b2fd53b24e9235838b07f1d8cb1d2f3d5ba62c0ad5a1791e0\
   fe79f6fdb9f49910274aa184855b67850ab2a53b39b131d07bc3d4e80a4f83b1c9f8\
                                                            f5f97f1fa598



Tschofenig, et al.      Expires 3 September 2026               [Page 49]

Internet-Draft                  COSE HPKE                     March 2026


   HPKE-5 Encrypt0 with default aad and default info

   Ciphertext: \
   d08344a101182ba2044e626f622d68706b655f352d696e74235838a7887685085eef\
   bcf8230ce60ab6d18c01044807413f38ef1203b73b8083d37c3474fe2e822945c77f\
   a011a4c808f55fbed005c8e90a90e4582101dd9b944c4e051fa9214aa99296a83f81\
                                        c04642f1f6aecd6f9304bbe5a92954f8


   HPKE-5 Encrypt0 with external aad and default info

   Ciphertext: \
   d08344a101182ba2044e626f622d68706b655f352d696e742358388cde9ba79de945\
   37b33e121f3c8d3c5a720c9d3e5eaad0f0e0f84e323d592d20afa87a09657765d5ea\
   57b27659366cfde26a80d817e5b6ed58213794aa4fbbc9807f953c23eed30e575d16\
                                        e83b488a521b03a7e737ce9a6f7e90e4


   HPKE-5 Encrypt0 with default aad and external info

   Ciphertext: \
   d08344a101182ba2044e626f622d68706b655f352d696e74235838ca713a0271741c\
   ac564ae35b5278b343ce9b3f0f2a5379a0f20f6f759b682ad9884926185e7f2fb9db\
   a541bc2a41034392e430c3f429f16a58211b393d9ba77bf79efa231d87033cf8a407\
                                        ba249891c098abf834b63e222aa744b3


   HPKE-5 Encrypt0 with external aad and external info

   Ciphertext: \
   d08344a101182ba2044e626f622d68706b655f352d696e742358388c4b45493d8b3a\
   5cd88bb3022e3e0a3777ac3b5f480e448b509089bb801608654a984e85200a70476f\
   206b0bdf045063a57f472d63c69b1a58212a35247d2dd06d3bcdf02f6d26e751420e\
                                        a966907612e4431f44d7f792e91818a2


   HPKE-6 COSE_Key: \
   a60101024e626f622d68706b655f362d696e7403182c20052158380aff5f4a86fc46\
   8a25b7715d066628125dad13e4243f242cd6585f89f7371a55cfc3cf42cd3405a78d\
   d380b4e9f4d47880c684deaa3f8aa923583898b6c98f0d48162ecc4c0f5e09c97246\
   b03564a2672e12496f0f7a0d0576fbbdfb287b5a868e5b569a55b7d3765e5685feb7\
                                                            270471b13392


   HPKE-6 Encrypt0 with default aad and default info

   Ciphertext: \
   d08344a101182ca2044e626f622d68706b655f362d696e74235838a17baa842458b4\



Tschofenig, et al.      Expires 3 September 2026               [Page 50]

Internet-Draft                  COSE HPKE                     March 2026


   d082f042e5598e072bbe19b9970963ca0428a577add73c7a8d275e63f53971f4ba96\
   bf842201d1c4776122dfffbc04e6cc582157e46f77fd6c2f2cab3d0810d67b7eac73\
                                        41c0726ebaf978a8fafda78f295fad0e


   HPKE-6 Encrypt0 with external aad and default info

   Ciphertext: \
   d08344a101182ca2044e626f622d68706b655f362d696e7423583851e914d34210e5\
   fe233283c2755b6a42cfb1ada1139d9ece7664e57336b03892bdc67cec396c13dae4\
   37801cca5c885901fb616a96166ce75821fb3979eea60600d09bb76b4f3a5596ad5b\
                                        194b21e713070fe7b0fa1443b809f65d


   HPKE-6 Encrypt0 with default aad and external info

   Ciphertext: \
   d08344a101182ca2044e626f622d68706b655f362d696e7423583842ad024c1f764c\
   bb797b3558d9c8ed9c3559c65870620c7b56f3367fdc65bc7b696d96411b57cd47a1\
   56fb945a939aca63f1a168f1a7d96a582197c449697f868ac6a708a8f9a1b1c32537\
                                        2edf6333c87e8d5f1853e8599a7848d2


   HPKE-6 Encrypt0 with external aad and external info

   Ciphertext: \
   d08344a101182ca2044e626f622d68706b655f362d696e742358380a100686fd1f04\
   0155a64da572a9e9109487a55c7fed63c68c7bb38311a7b9c48d1555e006f0db2884\
   bb4306703a9c5cb7c4a0e4afd1297b582199c40b5fcba3fa474ebd9f44326e308b46\
                                        2a2171a5c50294329284f0e333ed5f15


   HPKE-7 COSE_Key: \
   a70102024e626f622d68706b655f372d696e7403182d2001215820df717fb8deae1b\
   58b754487c5432c8ec9a140dd11bcc7cd65cbe4b728e9263d6225820a8528d614367\
   3203144a9636ea065c60761390916f2218c8db958a64e263d3e02358202343a73ed3\
                  dc2b5e110d734c8d5e7a8b7fea63849e78a8db3da48a65ecdb720e


   HPKE-7 Encrypt0 with default aad and default info

   Ciphertext: \
   d08344a101182da2044e626f622d68706b655f372d696e74235841040ae250a36575\
   d60ebcd50444d99d1f1546438585fc807338d0a69cffad14d45b28047e5e4d7429f6\
   28e9f8313058535375dcf1ce1804a83b8745b2d63064cf6b5821847f648fbeb8e386\
                      89248933366fe6929e36843d7855e318c48383f54022b7bac7





Tschofenig, et al.      Expires 3 September 2026               [Page 51]

Internet-Draft                  COSE HPKE                     March 2026


   HPKE-7 Encrypt0 with external aad and default info

   Ciphertext: \
   d08344a101182da2044e626f622d68706b655f372d696e74235841046a563d7eea74\
   4ccbacc9ea6df50e002d8b235fabc7023d51c75e5ba22af4102c1c20954d6cc1b2b6\
   3f893d504301c94fc37ba89084d04ca59f96581d87435f215821d619e5c0189533c3\
                      9c353cab4db8a939225c170e840915b27503b9de88f5451beb


   HPKE-7 Encrypt0 with default aad and external info

   Ciphertext: \
   d08344a101182da2044e626f622d68706b655f372d696e7423584104e5f56b98441f\
   710117e3d9019b5d09cde61b1d4f228353062b8a7667aa58dab2e511b922f740eb7b\
   8850a5a838bcb6c16ddc1cb6d7000e7d2e2d69867e11d73a582107834d1f44591c01\
                      db20acb0d7f71faa793e11f7c83619a9410a97991eef3a56eb


   HPKE-7 Encrypt0 with external aad and external info

   Ciphertext: \
   d08344a101182da2044e626f622d68706b655f372d696e742358410472587451cdc6\
   5749b6724a78484c69e4a7092edec45c31aaf13a1b725b388820efb2b381bab4b52e\
   feb9d6d65ff69c49b765426a6a4fd7872b3691149069394a582142a32c0ba176b205\
                      3b114682189982e07506a4ac383067aa9920552e452be123b8


   HPKE-0-KE COSE_Key: \
   a70102024d626f622d68706b655f305f6b6503182e2001215820f135aa53a7b8d080\
   1eefc6545a8b6262d74b74015f246c11b37762767ef201ff225820ed6afc34bc882d\
   17d025cc79723caaec97006411b6b975add484362196948c4e235820182a2a509e56\
                    778bf678dbc5ca76cc18fce47300815540c82d4a624b17bbe437


   HPKE-0-KE KE+PSK with default aad, default info, default hpke aad

   Ciphertext: \
   d8608443a10101a1055055ef57a8c8f1e2cd792f9e9c253a7adb5821e7dde67c8df6\
   36eb9b2349527a6bab7bd575e46995b3cb45b7edfb339ef6dbd903818353a201182e\
   044d626f622d68706b655f305f6b65a1235841042436c6d0ff2176e1a1a808737781\
   a7fc7376014919b539aace84114fe6dccfb82c327719721efc5e8df87cebe7d0c28b\
   74770a2c816781a5c88f8b6ef83110a158204ca4cc64d178000d42aa6092f7c8ef5b\
                                        d5995a33ef7c4b6d9490b105215d6293


   HPKE-0-KE KE+PSK with default aad, default info, external hpke aad

   Ciphertext: \



Tschofenig, et al.      Expires 3 September 2026               [Page 52]

Internet-Draft                  COSE HPKE                     March 2026


   d8608443a10101a10550ca918484db7e57fcd6a451579d04a91058218f4e49d4242d\
   4b03092402de93ba613f64d3546334581d75f09781a917eb64b5c9818353a201182e\
   044d626f622d68706b655f305f6b65a1235841043f245ce79f1a6674314e44010377\
   c817b3e52e31767c45143824ebdd4275a8c02f6037267b7de937ef1e3d5331000305\
   0311b33826469b3f7213a7d3a518d1b95820efe256263376b60f788d17a590b31464\
                                        903587f5ef8708016697bdd27e793424


   HPKE-0-KE KE+PSK with external aad, default info, default hpke aad

   Ciphertext: \
   d8608443a10101a1055008d4b4ba3a6b7fab94fea740ddfea6ae582145dfe705c3a8\
   85a23c92abce2e9a4ceee4913ca54c12e3c7df39a5239012ce15a1818353a201182e\
   044d626f622d68706b655f305f6b65a1235841043e734095428789dee24b83790686\
   3ad7bcef86c3fb6c4839eb76463a081dc0b1c64c504ecb319ae0c64f6a6a8b7294a5\
   b7d68c2cd12493673ecb9719a01343e7582061aa26e99c15baa82edd40265236cad4\
                                        511aa05519617cc0c22f56d455ec7e26


   HPKE-0-KE KE+PSK with external aad, default info, external hpke aad

   Ciphertext: \
   d8608443a10101a10550db52db662f81a9ae2c1cec60b79abb125821ff4bf2e65f87\
   d17e74432da6da46f264543c5662a34da8b1d63c7a04f92cf4a2e3818353a201182e\
   044d626f622d68706b655f305f6b65a123584104ac44c7268c1790ef423d607b2ff7\
   5320667e20695387db9c1fe7ec4bb97b74001f33dc58c9e56353bc67a4d6820226cc\
   36e98452e912a325755537a6429c65e9582043c8fcd50f343797fc2350b7e22476a3\
                                        9b6370fa338a7f8cb90df438409b407c


   HPKE-0-KE KE+PSK with default aad, external info, default hpke aad

   Ciphertext: \
   d8608443a10101a10550b0d6c7caf307e05561f106e44a54742f582143713d533c1f\
   b2c96071d30efd30633d18ed3891e3cc6338d05fdf922a1fc82ff3818353a201182e\
   044d626f622d68706b655f305f6b65a123584104212d6e5b8b376b279515d1337519\
   7b64d18b311d1adad0df5c72480ac5b4ce87c68016824b2a952c745132132d417498\
   15d7696a117d77384188fdd7cc6176f9582059ed1ddcfd922588e541aaaf4bd89f70\
                                        a360adfd109da2a83c5eb7b20732579c


   HPKE-0-KE KE+PSK with default aad, external info, external hpke aad

   Ciphertext: \
   d8608443a10101a105506024ab7fed3cf00950e794951efbfe415821eced08e89a89\
   e6184147e56c1650fd57ff514233042b6e9001170dbc060a66ab89818353a201182e\
   044d626f622d68706b655f305f6b65a1235841047aab9097da3d4c17f4bb5504d8d4\
   5f4c28ebbeccccb77b2f7a4f8f3674700554578c7a0f19586a2cf4fb0cd5926eb0e9\



Tschofenig, et al.      Expires 3 September 2026               [Page 53]

Internet-Draft                  COSE HPKE                     March 2026


   db6733752e4f43dd9bd5996554e522ba5820839a506ff751227d9ec4db931f73517f\
                                        65a3ccc9d84a9595c06f7cf07fc6bd19


   HPKE-0-KE KE+PSK with external aad, external info, default hpke aad

   Ciphertext: \
   d8608443a10101a10550fda46441c4560291a6eec9da655289de5821a6b9b3342ee5\
   49f2f6dee9ab165d7631cb2a29f0d923378638cb7f5c8e648a193f818353a201182e\
   044d626f622d68706b655f305f6b65a123584104b378a7e3362bb1becf24ae2e8562\
   66da9784e20f7aaddda2a536cc355595d888e9737891b32e29c3ab5c07eb55e4f44a\
   2631529f9a2dadbcd1c5e32d8fa46ddc58203b391f81a9aabb2683dc6a371d6824d7\
                                        8812595cba6c97fb83798fd87eef75c7


   HPKE-0-KE KE+PSK with external aad, external info, external hpke aad

   Ciphertext: \
   d8608443a10101a105507a78d1bfef768bd0739fad341f49039658210a5f55ba415f\
   a3c240ef60eab590bd91cce926c92a8762e9362bca167fd8fad844818353a201182e\
   044d626f622d68706b655f305f6b65a123584104df01fe0e86de46fcbdf83569d3be\
   4892fcbf66172b953fa5af4a4da3175b825a0a68a2497f779dae5430522942e77518\
   4c0403b6a3f57b5c49ea93775667c86c58204f835e149377345d40bddfd3e7e24793\
                                        19518a11b44ede7f24cfd059652094cd


   HPKE-1-KE COSE_Key: \
   a70102024d626f622d68706b655f315f6b6503182f20022158304f65f3e8ce5db1ff\
   24f49fe236ffdcfba3214bde3c1c0bdec78d6e35b0d59d15edb4f497a1b440c7e37a\
   29f99de5bfb922583076653c742f9eb5a42d6d4f88a01ba09cb8cadad0eb570b312f\
   60ea5ff6aec15c927af3fa6976c77dec3141b893a9a697235830ec601bec4dffc923\
   9b6a0bbcdf52c9acf322a125af9658b4d145a0d2738229f21f4454e4f4a18e5c2240\
                                                            437e66d0f6bb


   HPKE-1-KE KE+PSK with default aad, default info, default hpke aad

   Ciphertext: \
   d8608443a10103a10558203f9020bb7917aad988ac4ce28ba557125cbca073f47b92\
   d62ac626faea8e99d358219db8e5036cc04c9c1fdca5193d326bd865c2cf17f26a9c\
   7389e8f3db5d48753896818353a201182f044d626f622d68706b655f315f6b65a123\
   586104b224dde0932ad62723c9e8898a4c1559aaae3a6b13ebad3e39f956219a98b4\
   25430f04b20c91d206e09fc2444f9052f5683f37ee65fd3848fe7a4dc1f76add725e\
   3017e83c8d12a84845cd1d2d82d1166ee680a1bacf199a73031111d84e948858302e\
   5d980137bc7495b6a0d6b71601c1a1e75256df9d629fe05fa6e62d42e17ddcb008f3\
                                              62b52c2febd892232e16c2497c





Tschofenig, et al.      Expires 3 September 2026               [Page 54]

Internet-Draft                  COSE HPKE                     March 2026


   HPKE-1-KE KE+PSK with default aad, default info, external hpke aad

   Ciphertext: \
   d8608443a10103a105582037216bdf248d82945b87a3c84435f20301e9df3b374406\
   88d24b21679a7a0ab85821a931981ba8d07236e891fbb39c0618999e67c80f6a2628\
   23a6d129c56aaf4d508c818353a201182f044d626f622d68706b655f315f6b65a123\
   5861048cd2c5b128525c051760ca792ae38c60f5d9be83091d4e904eaca8e0075df6\
   d8f30738de090c203535bebcf1a6e9b6bf36e224bcd8fb5967e0a0eca0a0fbfdf5b3\
   5da3a69e3c7caac50f266a3fc11e42d087511f1b0fad6d523ae53a0bfe604c5830cc\
   cd606f644126bc917ae03ba7cefb34a38a8a4e00f51b830fb459018b009c78348094\
                                              1f73800fc8e0b112002a07fc52


   HPKE-1-KE KE+PSK with external aad, default info, default hpke aad

   Ciphertext: \
   d8608443a10103a105582066815f04df75e4baa646152f2460695b200df8a50bbd0e\
   299dafefaf15c0532a58212dc67fc86f0206f279930dced3b6dfe726250cff8354c0\
   b657fe6bcdaa6488daa9818353a201182f044d626f622d68706b655f315f6b65a123\
   5861047c52bead4335a216813ae6e4dee2659ca7105ea850317c25b0cea602c8f3f2\
   2e0141b58893ec356f33c20d6330bbaf836f158ba1ed714a04847a7813c64ac6c702\
   9674035b6bca9c78f558746e669627970d8ac3b87800e4afe2d64db3dcb57f5830b6\
   6689f6f4d536439d6b2e3f8240ae704c17679f94c63590fd6a29a03b1e32d40e2af8\
                                              e664f622d0e5877f002882d558


   HPKE-1-KE KE+PSK with external aad, default info, external hpke aad

   Ciphertext: \
   d8608443a10103a10558209eddef4455129ccbc494aff056fe52b251224e272da90c\
   7ecd54ce94c7d45169582188ace3811de11efcd2085d7ae48ffeaa7ce401e9c991e2\
   25044c8359190d997283818353a201182f044d626f622d68706b655f315f6b65a123\
   5861046ed1710cfe5f23c768f69ae5124ea8baa65b18a1981c64e157e8f324619215\
   c7878a697c004a612fe20f66c89b7b2af741cfb7e867b7c2a1b35273c2bc947ecbfc\
   868377795c296592759d3bc722bcd62bd1ca6e9fd0c70a9b16908da9b2c8445830c6\
   199481077ac37f2ec1d4b1ef1fef392e4fb9141df4293dafb794b54bdc4064a81d8d\
                                              8e373ad1d3e92e246066d5738f


   HPKE-1-KE KE+PSK with default aad, external info, default hpke aad

   Ciphertext: \
   d8608443a10103a1055820f47c3ba696c350eaf5dfe64827bf68b315ef8cdd02f6eb\
   79b86c025f16c9b4a1582197c7f2ecf7c3f2b716ab7d4b73f97b481b222e60716210\
   534f78016c9b03413f38818353a201182f044d626f622d68706b655f315f6b65a123\
   586104507accfed015dcf0df6d1306def2ceb0452ba174ecd3e06b9d30e347e07364\
   b3235ddd156f6501ab8f96a27ddd65fa2b0d54326b38c3bc6ccb592bb72a41561fea\
   fa7ba3d707a9f8723c96c0c849fac454603f148c45525dfa19582e76c9a0c3583003\



Tschofenig, et al.      Expires 3 September 2026               [Page 55]

Internet-Draft                  COSE HPKE                     March 2026


   caa89c05e657bc89efbad8e98477e85fb02ec395c0afc94547ebdca64d653e80923b\
                                              95fca02adf07a7e017693e68e5


   HPKE-1-KE KE+PSK with default aad, external info, external hpke aad

   Ciphertext: \
   d8608443a10103a105582018e63fad49110f7ca669baa530a3ec034c2f1770d1eaa2\
   ce2a341f217d896bb558211815fb8683836dfb3704d766cb4b40dc4b1fd3ac1b2d24\
   9f8bf391d3a555169506818353a201182f044d626f622d68706b655f315f6b65a123\
   586104a4f4e17c89b7c0b522e8ec28bd24c0bab416f94b30c5fe34ac861dfb25235b\
   67aa6e5b3a9ae6e716165091f673b89e42d34c159d3017dc6278c94552927b864c18\
   918855547bd105e52143bf40d918ace0909d175c4762e0148a160db874ca0a5830aa\
   4d85b740d6f6374b5e2badfee77f4785b09fb924f08e66f5fefe36475452c4afd6b8\
                                              21d2709f5475a4f2e4e425757c


   HPKE-1-KE KE+PSK with external aad, external info, default hpke aad

   Ciphertext: \
   d8608443a10103a1055820ef49dff5d5ba7d895181eb84e0559e17064ff6149bc74b\
   3b1cc707edffb10ed058218b25783a9d5efebf68c9a32535d50dea5335af4b28683d\
   ddea0238b7ac864efe65818353a201182f044d626f622d68706b655f315f6b65a123\
   586104acb79124f34d2f82b6816d4ef4f835f6ac056fa3ed49b631136e416de1a7da\
   5b13d77ef3e99b5c3af89c4335fcec4d0b52063e3669de03469d8f65069dae4484cf\
   58027f0d1c0414575db5e4ae47d302f49aad5d6efb7eb1c827502688f245af58306c\
   ca7863e2e0b35193bad7c08677f15c9497ed073df29ff1c7acb784a2d9d5c5184d9c\
                                              8ef64218d1561a9f36b7c38d09


   HPKE-1-KE KE+PSK with external aad, external info, external hpke aad

   Ciphertext: \
   d8608443a10103a1055820b6813d3b91fd420ce0fbb282282a0781e928bba1f2ed65\
   55ac3876ccb79139605821278ef63f7bef40a20188e88d8072a35fa49b421dfc7106\
   9a0f01abf8632b5a188f818353a201182f044d626f622d68706b655f315f6b65a123\
   5861046f6718ba3d9581817b7d6e8ba572577ca2b4c426db2e83273af0b8bbf1ee33\
   d54afd913c341bbb8d3115d7b6d08b6d1fee711131c1c908877accc0214cb2c86670\
   cfb647cedc0d3de474397691ff71a9f72ddfd0d8a7bea15c6ab8b1035fb723583013\
   444234c83126f8a62772aa4b9a6e7a702255557cd726a740ee18a1766ad48148d00f\
                                              87f6e9d418d3c68f8f8411b77a


   HPKE-2-KE COSE_Key: \
   a70102024d626f622d68706b655f325f6b65031830200321584200d79ba4c6f1f0cf\
   b40eb165353f19725907afc3d302e466f937fcd14fb3be4eb50e2d13502642e691ee\
   2f9a6ff8f9639f2af3291fdb7c3b4c2d48b9ba6963d7762e22584201d842560d1937\
   0441abf9819003efbe8ebfb6ea2d6c53eff1952aab6abd9956aa8d35642bd3b1fc8e\



Tschofenig, et al.      Expires 3 September 2026               [Page 56]

Internet-Draft                  COSE HPKE                     March 2026


   99e5a55a8e5615240e1f5c8d3e83481307215f71d7eb06734b23584201565854ad14\
   06345de77c2a4df3715f29c2bea30b86c08ca2b756118969f5c7aeea0ed0aa10ce20\
                    5ccb5428e4ffb476bf1524a3905ecb7381fef8c5011e5870b9f8


   HPKE-2-KE KE+PSK with default aad, default info, default hpke aad

   Ciphertext: \
   d8608443a10103a10558203138bee2c7c5222a490f6dc8afc1b3928d44db2df56fb4\
   032acfe1079ff9c52a5821093d059b8e0684b04d4a7a4eaeae24cbea063414467e45\
   89417511e7468410298e818353a2011830044d626f622d68706b655f325f6b65a123\
   5885040162b43abd5b8846801b7de98072cb9603536ec3a7bd30668528dc75707804\
   dbca8a71e3adcae9ad7635e1107ab85441b63acb86d0252488ac7c24157460955da4\
   22010eed01508bc178962b45cb26d06d484ee72b4ac2cfc937e1d171e42483a5a5ac\
   080b83a0aa25b376facc15607d9a2ef91ebd233e2f35ef08b4dca8fb0efbe1676158\
   306417055e20b3c85bd42c94377af8ff21b5da0bacd1f62da7e0b91499158eda595b\
                                          40d1c9fe83361bf739577e2cc7b847


   HPKE-2-KE KE+PSK with default aad, default info, external hpke aad

   Ciphertext: \
   d8608443a10103a1055820215850dbf837415f3822d8f5d26cd15a0c146c92359b11\
   b1782867d457d4378a5821dca9a96193d94c1d1a6875471f113dfa4c623fd0ce711b\
   f7d4c1109bdf7930895b818353a2011830044d626f622d68706b655f325f6b65a123\
   58850400c6e8136d09b7a8acb620c13b17ac1afef18ed180cd259be1d3dda1072d96\
   40371b05e7c56911fa97aeb1c7ad54c8fd396f40e75cb5f67f17a2ea70e873b56f0e\
   5501372452c80572470b4cc341434b023b8f7d421ef1a6560670d9ac7510dc6d6cc4\
   4d4c2454ef702313759494bd5dc1198aaee2ba8005bbbcde75d688f59b15a88e1f58\
   30c17f1cae979c5ce953c68b778f0a774bcee5af484f6c59c35cfef9c811cfc87959\
                                          334a1c4475034e2b780ec7bb53499e


   HPKE-2-KE KE+PSK with external aad, default info, default hpke aad

   Ciphertext: \
   d8608443a10103a1055820fdb5784ac8e133937727e19374513e964a7d940e4f5684\
   b73ffccddc843df4445821abc32701a38c1c36b3cdd98683474ac9d01237f4a61013\
   7905c75be8520a7e7a4e818353a2011830044d626f622d68706b655f325f6b65a123\
   58850400652d2c6aad232448534aa1fbf6318956a3ca8fe3a581bc264cfb74b5c4b5\
   9675b5852f7b28c515413414faf01474c45c4111711ffab4d1541cfcaaa0a6136dbf\
   78017cdab90f57f246ba74fdbad5218bb7e57e4f645253c3802417f91587beb94af2\
   3423eb0fc295c74b42fe64d5c033bbf29a3b18548788de1010bdcc076254dd30ed58\
   3063e1f93cb9087ee33598b22f6b5f77008b4798345c4a8004b42565dc5a753dc39d\
                                          280117494fec9fb5ae0e28ac358470


   HPKE-2-KE KE+PSK with external aad, default info, external hpke aad



Tschofenig, et al.      Expires 3 September 2026               [Page 57]

Internet-Draft                  COSE HPKE                     March 2026


   Ciphertext: \
   d8608443a10103a10558206a802ccb1bd4d388862b5fe0afce78dc7fc3c08a4ee1c4\
   97fc03e2a92db02da45821329c4d048a5c81485fff9540d9ddc083d31b59c6eee09e\
   8b3787e0f50424eff01d818353a2011830044d626f622d68706b655f325f6b65a123\
   58850401f32ef361c8b9435fd85f2a762bff35d49407738e645893bc38938a046553\
   9beaa0867b3c32eb993ce0a8599e684b22fbe06527d7ea5f23809bf2a340e4310bd9\
   20005d05b63e8fdaa1428ae3bbf70e8b606b8bb364c897a1edcf54d27e56dc0fb4e4\
   c89b35099465048b10531dff3101167eb081f4ce1198d66361773ce83f1420cff658\
   300189869866e44e995db469e07664386d86680cf0afba7ed0506d893124347ed12c\
                                          05277d04eb5ca818a83ef7d2abed40


   HPKE-2-KE KE+PSK with default aad, external info, default hpke aad

   Ciphertext: \
   d8608443a10103a1055820ca66488980e271eb113bab9c87c532ab964778274b14fd\
   d1498f43760660cbdb58215915445e1b1592fc3ca8a10e066770df837e8dcf627b2d\
   cdb303350a8cfdc15181818353a2011830044d626f622d68706b655f325f6b65a123\
   58850400af9a27daf713ab290e06f323585fe4e378adb3da71ee3f913d4df0ff6432\
   34d5096298388e0385b6791583dae223df7a2395c739be3456d877f2c22a60db7079\
   3b019e97cb108e5ed8a4dcc92e708f9010f0ae64410aba36ef66edb45275f4c22e61\
   3352d0ad6e2a94c645ddca1c3db4df47b0453de357c91f6dfafacb11221462060058\
   3060acf6929d7bf0496ef34937a3bea4a83b92e7ac223b9cb7b1389eac5a6fe52f62\
                                          a7e16186005c5d9c7e3aa052b66c4f


   HPKE-2-KE KE+PSK with default aad, external info, external hpke aad

   Ciphertext: \
   d8608443a10103a1055820c12e10e83ffb5d684b5dbc8987f36227b0ae5356f60eab\
   1c5cfc07733972713e5821625dad1ac818ddcd4f5847d09b661f6a80bb3ee80c85c7\
   11d1eb1fd57e6b6e9bbc818353a2011830044d626f622d68706b655f325f6b65a123\
   5885040163399875d2f44c2b62f6a241dc4e5d2d77ae2f71d48b8a4ff7015cfea98c\
   25573ca31b1fecc15ab570c6d848a9dd6cf65791cebd6fafa43b85a997caae43a6ed\
   6d000f7b7e6f33ee305779bcdb560112e82663715bacb5b5b46a17e00fbc1c7e48dd\
   eea2cf7f79d6a8db02baf64ec466244d206ae933eb4ec2559603a306c5a43a36f758\
   30151440d327f5b4301017aa88a5c07df896c565e5dda60e71594c9a07dd95d16ea9\
                                          7f780977fe2b5e1ec9a3bb2899ec0d


   HPKE-2-KE KE+PSK with external aad, external info, default hpke aad

   Ciphertext: \
   d8608443a10103a1055820d2d3de0c045b580ca7065a0b6ee0ee4a99b16df064c8c3\
   b94f080503ae1bf96b58217b530401f8dfe8b7f938929169f31054f4c1b077d874da\
   e6357e0299523cf309ff818353a2011830044d626f622d68706b655f325f6b65a123\
   588504001c84d1eedbed866132867ed9cb7468462f9c9a149fe92f8b719d6b2c02c1\
   10e04b1cefbdf10604a0426a24e0a11b2f1b519b1344629344a4f54bc0fe2996e9b4\



Tschofenig, et al.      Expires 3 September 2026               [Page 58]

Internet-Draft                  COSE HPKE                     March 2026


   9e01478110bb40c4050e47d7bb2d2f99233dbc6bb71a1a60a2ccefde398fd6eaaa10\
   c940825ef3f2bd824399139b9f55ba7d8c0f600c4208867778f7bd596c3c95afc758\
   3063330387cd24664cc5ebc2ad1d1f9e785c9c1c8682ab61e810595b99f6af562ca9\
                                          751eaef8949b746005a8aabb3d73bf


   HPKE-2-KE KE+PSK with external aad, external info, external hpke aad

   Ciphertext: \
   d8608443a10103a105582035a8bd741dd4bc4eb339dcc69e91214badd6d79fff2cca\
   4088e6733b80f7d4e25821a2b8d2e530b9939d2bc3e478ca797afb14453151e294c1\
   dc4a2bbaba356949dd95818353a2011830044d626f622d68706b655f325f6b65a123\
   58850401dfb9d20c07e0ba4fcc4b93e66bd94ea0b8ea94f4b336912b0d676b5367d6\
   97801e668f598dadbfbda8c375478d368209e09d51f7cfa2ad283f8d211ae13b7d23\
   d801b2f56718deba752f33c8ba0aef918db14d6b901ac55072a781eb26b04cf55363\
   461604f6b0b6931f0da446f5d55fb56c82ce6989fc88129b1918335efd0fcda03558\
   30afc3fd0466c8696180429b63cc76880e877e2da59f20411572cffe8ce15ceff86e\
                                          78a18472c78a6286127290caf6f15f


   HPKE-3-KE COSE_Key: \
   a60101024d626f622d68706b655f335f6b65031831200421582032df6a916a5f6f14\
   5cacd3755783f65f7f5b35ddfdc6bbe6e699c1012f296c70235820e8acbd4b527e76\
                      6136f0e0ae266dafaca435e2c4326f6be8aeeea30d4ce91070


   HPKE-3-KE KE+PSK with default aad, default info, default hpke aad

   Ciphertext: \
   d8608443a10101a105508fde94810cf9df2b8f3e011dd014866458211e3b36874e1b\
   8fa028f8805bbb1f88cd29125b6cb229292eed3949060323114f26818353a2011831\
   044d626f622d68706b655f335f6b65a1235820fd114c5c260726726405b3983e92b8\
   24c76ff415bfb3a85d43266be85e436d605820db8a62e96f13814fb6b391fbd07868\
                                      7ec01e5430408a1ba130b8aa561106d36c


   HPKE-3-KE KE+PSK with default aad, default info, external hpke aad

   Ciphertext: \
   d8608443a10101a10550e7eb3c12fba8f1a84360649e00228c035821188af3afa5ea\
   10ee723e40b0aefa2a7c1b1b05ca778c613ecc0c1f846595a5a7b5818353a2011831\
   044d626f622d68706b655f335f6b65a123582020f2e48c5b6cd52cc560c8c345050f\
   1bfd3756259bbd321704a963614646656c582002ca2aca70d04f750f32805cfc440f\
                                      e78591f3a5c1fe6a931870ba6cad61244d


   HPKE-3-KE KE+PSK with external aad, default info, default hpke aad




Tschofenig, et al.      Expires 3 September 2026               [Page 59]

Internet-Draft                  COSE HPKE                     March 2026


   Ciphertext: \
   d8608443a10101a105506c5121bb87c9c2f62b2c868403be8a38582113c72fe8aba5\
   5de94b9f0cea23854e8fb4dfdf87d034f0b17e366fb05f94be4364818353a2011831\
   044d626f622d68706b655f335f6b65a12358201cb2a61bbc134a03b6ba241f0bf47f\
   71a65a3b67e948f7974f94e05e2569c97458209e8495b63496b92c5bab86e7f34b55\
                                      5b6a3677397bf408835500188c3df93b39


   HPKE-3-KE KE+PSK with external aad, default info, external hpke aad

   Ciphertext: \
   d8608443a10101a10550f9a3efc56621cd0fa9c173feb8d486ea5821bc91169ed9a8\
   17fefa394582affb4f019ecf50cdbfc46e52ef437d708907854447818353a2011831\
   044d626f622d68706b655f335f6b65a1235820e33a5d0f7a885988058daa06eb6895\
   961f41e6b93e07314e8319ec60dd0ca8635820d38344948ce6c0fcae23835a7b3059\
                                      dcca67057ebbb3628b30c7a44af246ca2a


   HPKE-3-KE KE+PSK with default aad, external info, default hpke aad

   Ciphertext: \
   d8608443a10101a10550e21e4f3f711e3d4a40233210b6c7cb18582153dae8d74b8f\
   f4377890721f44b576e9cde9c069796daa0ee1606b21b868d72560818353a2011831\
   044d626f622d68706b655f335f6b65a12358202d4c865b322326d0c42970da331d64\
   0be580266d1ff5bd48fe2d5851bac0fe7358203325793599c3f217f84542bc2523ad\
                                      beec95c931eb53e71145f1a3f8f78843e6


   HPKE-3-KE KE+PSK with default aad, external info, external hpke aad

   Ciphertext: \
   d8608443a10101a10550784f25d8b3b8e28c2ee57f8034c2d63558213d35627b8906\
   a2c6325f0bc1dcbeff96a66f00d2326b7bc347631f356dc79a1c37818353a2011831\
   044d626f622d68706b655f335f6b65a12358207ebbf54428b2c7ab5cfbb1aade2cc6\
   a9556a0e58528ae576258f0d7c126585315820b610571bba5facae1b75386f5ee98e\
                                      3c370fd7b7070b58794e4ebfbedd876543


   HPKE-3-KE KE+PSK with external aad, external info, default hpke aad

   Ciphertext: \
   d8608443a10101a10550b0e54f4eb4dbc8d74d0403151a4c9ab65821bb0bf21a799e\
   13f522fd5d6efd495e1e0715ad541388557b9baaabd6c4f7105280818353a2011831\
   044d626f622d68706b655f335f6b65a1235820bc2dd6a7498209f6a16ce2cb8ad311\
   46e1d7601f3b7a7d916e9b8f0c4b280c1858206335338627bda61773b8abc05330f2\
                                      d86744561fc9705df85392c3979a34aa82





Tschofenig, et al.      Expires 3 September 2026               [Page 60]

Internet-Draft                  COSE HPKE                     March 2026


   HPKE-3-KE KE+PSK with external aad, external info, external hpke aad

   Ciphertext: \
   d8608443a10101a105505e5a35587511620d9c95dbda458414285821ca24cea1349e\
   a1bd6610cf7d64fbae3809c17b48870a1e33fae2daefe83b16caef818353a2011831\
   044d626f622d68706b655f335f6b65a12358204f16be73404f6130ce36f25b3abf38\
   f1f8d574330257a3715a44182d74611c715820cf43a27483d12a7fc5a01ba05cf0b7\
                                      9bc9fb6c5b7108f7469c2ab8fc437d514d


   HPKE-4-KE COSE_Key: \
   a60101024d626f622d68706b655f345f6b65031832200421582000c2029ec474be36\
   8261a61ef7dc4a3cb7951209fcc66dbab39c14ff85400320235820d01a98ed714cf0\
                      8ad96c793edbae5e1f5258dd98e94a1a94d6a08adbd56ea74a


   HPKE-4-KE KE+PSK with default aad, default info, default hpke aad

   Ciphertext: \
   d8608444a1011818a1054c2fb741d0c5c6977aaa2b01c35821b738d24609bcaa98ee\
   1f5f7b77eb38b9d64e5aba602154c58c12c61824631a4f0c818353a2011832044d62\
   6f622d68706b655f345f6b65a1235820a2310170dbec7095eefb7d35107c425ec256\
   6a5e859cfd80e6a56fc91cb37e3c5830635a41f1026dd93b27b73d30c9a5391c7e05\
            bfc8b0ca766933f62257781c79fe6e4c2c0d1cb17edaee344fc33322a9f1


   HPKE-4-KE KE+PSK with default aad, default info, external hpke aad

   Ciphertext: \
   d8608444a1011818a1054c3cf3405adaa9331e2706668458216e3a5631d75766cb70\
   8fbda036a6e5b654f4bc3c19bfcbb7ad9ed3e5574115381a818353a2011832044d62\
   6f622d68706b655f345f6b65a123582009fe08cb84624452f285537cbc0671477338\
   7689960a3584b05cbb4ac70acb705830db74a5f8b12ea239755500670d38b3c63eae\
            4a1f0ba21b25876c427422a70a7f3cbf26a43570d266d28418c914394d2f


   HPKE-4-KE KE+PSK with external aad, default info, default hpke aad

   Ciphertext: \
   d8608444a1011818a1054c6d73414c64bbef1b945b35a9582118530c7ff2e58db941\
   e48ba7b1876e88a3e019bb1b92789dba0309cae6cb74ee2a818353a2011832044d62\
   6f622d68706b655f345f6b65a123582047267ddb7a6a5788a506b37d450aadffe786\
   164e6f94cf5253c8e023f181a73a583034362ce15946e700fd8bc9dccdf1cc504822\
            e76e2a9250866378e85b8d1c8faeade8e5657fa9dd9e36ebaa46c3ad923e


   HPKE-4-KE KE+PSK with external aad, default info, external hpke aad




Tschofenig, et al.      Expires 3 September 2026               [Page 61]

Internet-Draft                  COSE HPKE                     March 2026


   Ciphertext: \
   d8608444a1011818a1054c8bac033f30bf465b3c8184c25821ed9ea80bfb07d11a20\
   399d92e4d757179ae6e4ce1d9d5db67ca20fd0c85ffe35e3818353a2011832044d62\
   6f622d68706b655f345f6b65a12358200e6087d030b1e8520574f884baafdafddba7\
   1c558705cf4872aeca4629c7403758308f95cf34c40fb9ff6f3cae1f9a8e9f99058d\
            249f5feacb091b0e615e0e9f46a5bd1435439b1bd5844ee7775840003c36


   HPKE-4-KE KE+PSK with default aad, external info, default hpke aad

   Ciphertext: \
   d8608444a1011818a1054cc32577820e9fc7f1dfaaef16582146e402f02e4c45bf8d\
   e3c32d36b16f520faf735f90ab843f23796880fcbd549d07818353a2011832044d62\
   6f622d68706b655f345f6b65a1235820d524b1636dd7796be27a080a9167ddf362e8\
   a06eff5549572a04eaf9bbb46604583009ed3173e50ea69bd2a3f60a7252e81e1225\
            6016ae3a762b05e28174cdc853a80909b6f0be8db0aba24a48b2c975c153


   HPKE-4-KE KE+PSK with default aad, external info, external hpke aad

   Ciphertext: \
   d8608444a1011818a1054c733a1396a5fe52e4014a80355821d5b08336a933b87f03\
   26832badf4f522c942c95f0bac27c9e47bd99039360dbe5f818353a2011832044d62\
   6f622d68706b655f345f6b65a123582096d993edbd974f70b36f89a5833f745c5f2d\
   ba2c34e2dd25254ab4c3309078235830244a6ae5269b99fcf817f921dfbb914a3e7a\
            8d98d7effa565c1a38b6607c5ce29a0a6ea78cd3e00a1dc1c1191f715edd


   HPKE-4-KE KE+PSK with external aad, external info, default hpke aad

   Ciphertext: \
   d8608444a1011818a1054c6508d2450db84d5aafdf22645821979e63ed8bfdb38b82\
   8b5c495aa0eed1257eb0dd8784d52efc6acdb450ab3c00ec818353a2011832044d62\
   6f622d68706b655f345f6b65a1235820ff60abdde8677257c587be0228e616bfbbfc\
   b2ed5c311e112fffece0ae28d4585830299c4de0445f2f588b8f9dad87b10f5195bd\
            c20a65f1b0021c138304477ed35ed752694fde15c21cb4cbf5b49b8affb7


   HPKE-4-KE KE+PSK with external aad, external info, external hpke aad

   Ciphertext: \
   d8608444a1011818a1054c6a9fa48284941a3c00aaf7c8582173bfd8633fcb167664\
   09f713a4d6345c4331834876130bc6fa8e3b382914ec68b0818353a2011832044d62\
   6f622d68706b655f345f6b65a1235820a78b256072f458027fa9790f0689eb492f40\
   d28622e07c6ecb81fc30c02f894c583065f9ded5cdbc30262debac57505803bce0a2\
            879a354171668ef8378bad1f2e09e84ac1cc79fd7dfbf03a773a99d8a6dc





Tschofenig, et al.      Expires 3 September 2026               [Page 62]

Internet-Draft                  COSE HPKE                     March 2026


   HPKE-5-KE COSE_Key: \
   a60101024d626f622d68706b655f355f6b6503183320052158384e237eb6c934b5d9\
   48aee5db58e71b73becc1fdc6c90d45eb68975b0008ba24976fa622dbdf0848e80a6\
   a222e4b0e1f85b99631307bc4b01235838940bb8c6bf6882564f1138fc7805677a68\
   d2422492d3de009740f973e4e29cdd92e1942dd2f2d23526c410522376bc0c0890a6\
                                                              425097f4a9


   HPKE-5-KE KE+PSK with default aad, default info, default hpke aad

   Ciphertext: \
   d8608443a10103a10558205adbcb6e0ff034e4c7fb8f57d8684d48a0713ccd9d9ea8\
   07e0414efee28a983758212b781241cafbce0ddc141d16a4fbb48f64eb2aed749aff\
   992400a081c9719a3d98818353a2011833044d626f622d68706b655f355f6b65a123\
   5838dd342034c2bef0bb830c781530623f7dfae57752409b4c063c08c670bc5003be\
   86d45941075d2e38e35d6b5c8da084b1eba2e05119c48d26583023ec6199b0bbf9cc\
   776ea35e34fdaa85786090f62f738179128cb37aff35f95e5d12417ea84df23daef6\
                                                            eb78117a4f8c


   HPKE-5-KE KE+PSK with default aad, default info, external hpke aad

   Ciphertext: \
   d8608443a10103a1055820c801c70cd6c15c0ed4c5d31095a3d9ea5dd35a3b7ff85c\
   effb49ebac170a9ff95821ab85a76a92a692a53161168a3beb7a051346cb4859d3e0\
   f2047f9fe4c90131de12818353a2011833044d626f622d68706b655f355f6b65a123\
   5838b6c90aad8c11cbcb475b01f9544219dc466f6ec119d4108d35bc31cb12b2db26\
   e1c8eafc5362e696490c06129a5cb4f7fecaffa5bd0d00b958307a1ff17acb7d872e\
   c2bf968d6ecf7be5194175e98531359bc26db8a0293100649d3ff5dc80261c5c80fc\
                                                            1384c17e418b


   HPKE-5-KE KE+PSK with external aad, default info, default hpke aad

   Ciphertext: \
   d8608443a10103a1055820b55199d8da2f1d98276b8a6c0a6db64fde7f45c75fc468\
   10465cbe324072dee45821745d2621a784e938f5b81a742ccb209ad642502fb63210\
   0c3af8c2c9cbe013646f818353a2011833044d626f622d68706b655f355f6b65a123\
   58389cd5c81cf76b3be50a1ab36c6875d89b65f2d26355311f5c76c32ebb5fee324f\
   8faaa70fe97eaa8346edf8191529f21c58afe92d8dc56a3658309adba68d36c24323\
   0b6615bd68a7af1bc1ec51902ef11e4779dd2168fd515319fe60d7dfb4c0345fa9fa\
                                                            f53525a1d68e


   HPKE-5-KE KE+PSK with external aad, default info, external hpke aad

   Ciphertext: \
   d8608443a10103a1055820ada57fa4de7c380f19c3e5b2b929b64cd838f46a8c5087\



Tschofenig, et al.      Expires 3 September 2026               [Page 63]

Internet-Draft                  COSE HPKE                     March 2026


   3c7b84c076e8cfaa3a582185a638115f9e6036d3845bb96ccc12ff6d506200a7264e\
   524a316ec496d419c99f818353a2011833044d626f622d68706b655f355f6b65a123\
   583832dfdc226ec0637124dbf5a5c82795b860d0b80a1d6c50bbe2181ce1c8fccb7b\
   f4014340a3588af77a231124e7863278e44c082dd86495f25830d386e2f8408fcb05\
   d8898380101486ac601901774e065220f485f2049b11a01b0992f0ded73dfdb2341d\
                                                            4b53d6fdf3c1


   HPKE-5-KE KE+PSK with default aad, external info, default hpke aad

   Ciphertext: \
   d8608443a10103a10558205a2b4259c8726f7b27c76ecbab67b873b5d6d4a70b0cd3\
   486d71f14236b296e4582102e54618043019f8934c2c8c56db8d92189bf4ec1f5296\
   2bcf51fc02a965ba1440818353a2011833044d626f622d68706b655f355f6b65a123\
   58381213b34c1040aa5de533d5af7cc401a7824683762da048933a292ede982a9722\
   c6110351b1e98cd058705fbcca2818cff9f7b6b5bb8881f858305ab144940664bbc1\
   bf1c5b3c8c76d57520d871f7238b4cd34f8a53ff72b9980ad2d05a51403df6f8e926\
                                                            bea5780cf0c3


   HPKE-5-KE KE+PSK with default aad, external info, external hpke aad

   Ciphertext: \
   d8608443a10103a10558207f86dff69987f153f499c0511ed65e655d4d34430a81bc\
   95cdacc6a107f7bfd95821142a231e1c831730c99cb634850ec08c47305bb342b279\
   4ff27c6490d3d0c3036b818353a2011833044d626f622d68706b655f355f6b65a123\
   5838fc4618571971c112d55fef10f82d2114c2fb73dc0a94182cde7bfefea6d82685\
   b4bdfa1ee1947cf0d76a224c496f282e75694efcc4af5abf5830d074a192df2905b0\
   3183195149c13bf83c1dddbd2d76b40d5ef0ead641103b01ed5bb88de9a7e00e7924\
                                                            4343231a0207


   HPKE-5-KE KE+PSK with external aad, external info, default hpke aad

   Ciphertext: \
   d8608443a10103a10558201e95d431b06ea4021049ea2eaf75546ddf41f390ddb9e7\
   376863a904c769a5b058215929dd46a1996ea5323720abd290796727915d670e6bec\
   9192317d40e7e905be79818353a2011833044d626f622d68706b655f355f6b65a123\
   583856e102688b82fcd05585bf0cdfce4e7b749dcc4c8c5e5f0afffe1987accee459\
   369e30092519b382aeb395d121467af61fb7e344bc8397ea58301776ac6367407286\
   282a9f3bb645b42d0b77b35c17190bfa18489b5d11de38cebc9ae74e845ddbd76958\
                                                            38765da32724


   HPKE-5-KE KE+PSK with external aad, external info, external hpke aad

   Ciphertext: \
   d8608443a10103a1055820ccc5a28c0fc6ce3a77b3287c4bfa39527836d4d977ddca\



Tschofenig, et al.      Expires 3 September 2026               [Page 64]

Internet-Draft                  COSE HPKE                     March 2026


   2995f9f231c1aa3e5858211c8d84c7bc5b41632d045448b3dd303be1facaf8308dc4\
   520ecb141f366786903e818353a2011833044d626f622d68706b655f355f6b65a123\
   5838577f7fb7d14b3cbcf4cc8cc987c9fdb8c37e4c77787091720b16ca8ce1a1eb64\
   ff394100b5e30ebe141c1728c44bbe50111ed2b3cdfe80465830129a07f73d90eecc\
   a1fd2c6b57dde0cf7e35e08dbfec45195576143610932eb18a65a625d83ab2932861\
                                                            a06ffafecf92


   HPKE-6-KE COSE_Key: \
   a60101024d626f622d68706b655f365f6b6503183420052158387a73481c0220c785\
   b74d64c163e1de5d44e5390bd0fa08ee15073b58530e4085ffc8864e7a515d472177\
   58719376b1450d97bf2a669ab9b3235838dca30972462039bf863de85351d9190e87\
   938dfc8e84d55036d3ab77b8f8c75d9ce58b9cde255a254d70194cb4853134e6e375\
                                                              583df14190


   HPKE-6-KE KE+PSK with default aad, default info, default hpke aad

   Ciphertext: \
   d8608444a1011818a1054c36d04a7d19dc55e80075d23a5821e574da31d97960f6ab\
   7175d1a5532d59c14394e24f51df359de4db10b12714e9d9818353a2011834044d62\
   6f622d68706b655f365f6b65a1235838748632655487c9a95f46258ccdfa90d04f8b\
   434fa91810c86afacef5648cafbad2ed82ea7e2c2dfab8addcc335796fec210e0fe2\
   6ec10488583020b73a418c7419830b7f9d8b6e06a645b404fb35e6cd7ce7e7e74601\
                                abb1d5b66ed53e823517a315cd8ce27b2fd71a48


   HPKE-6-KE KE+PSK with default aad, default info, external hpke aad

   Ciphertext: \
   d8608444a1011818a1054c797818adbf0a654fb32d614758219fdd3c0be43a6ca9eb\
   b33af5563d90620ef2ae69bc9777c1d42862874b0a4ffb26818353a2011834044d62\
   6f622d68706b655f365f6b65a123583890100c00c48cb2531016da4f3a3d3094f1c2\
   f03451d76e992f540147bbd8e9ccc3b3538168856cd0ce5d772fdb299f9427793fa7\
   727d9dad5830cb8dcf359251188b60eca487fb14ee1c3914cf347c6fe223dbe5fef7\
                                d36de4ca2ceec64ba0a50fe5296451d51b53c4a7


   HPKE-6-KE KE+PSK with external aad, default info, default hpke aad

   Ciphertext: \
   d8608444a1011818a1054c82d73212f41a6d160736112458215de02558566868de98\
   6e6bd01ecba81b47bc67dab079c69519e9f020884172c3d0818353a2011834044d62\
   6f622d68706b655f365f6b65a123583842f56ab3e5441e6c65634346a2cfb13ae8b1\
   afc9a8b833d045045b57015f9e9ab7fafe6a05671e9ee29187e20cc1b5b0acf2a90b\
   402b5df1583078cf0aef816b9e8fc4f94678c98bfd1fd7999b5e44edfa2aecb64fc1\
                                5a17a94350eea486dffa00a9c7ca99224d46a09a




Tschofenig, et al.      Expires 3 September 2026               [Page 65]

Internet-Draft                  COSE HPKE                     March 2026


   HPKE-6-KE KE+PSK with external aad, default info, external hpke aad

   Ciphertext: \
   d8608444a1011818a1054c2a6fd56a8b3f6908e1111c255821b1a6735f8870342bcc\
   0906e85561781ee0126a5efe9aa8ed18d28533449f152e1b818353a2011834044d62\
   6f622d68706b655f365f6b65a12358388769dcc3b3ec1956dec6a7f75367a59c6387\
   0f2f7b3762ec7f32432495c5e73c2c23781033a9d364591a3d300426615e9f320422\
   35f42c035830604150f58d908a033a617ad608c6bc2ee2eecd55bd50571ff2472a5e\
                                523a09e2a6f85818c4466836d99331a35bc410a7


   HPKE-6-KE KE+PSK with default aad, external info, default hpke aad

   Ciphertext: \
   d8608444a1011818a1054c44d92785fbf3070bb1becfde58214c17f577725046e044\
   f809adda3ecc238d697c20e728bdcc4bb3720ad4765a5538818353a2011834044d62\
   6f622d68706b655f365f6b65a1235838bfc6a49e284186a6fa33ce0e7cd97e9b69f7\
   20a81559a4b3297705219bba25c54b0ab70cc38a1ddb67446c3e448167546c4620bd\
   8736a3e55830ea379d8848709112c1eef6366ab91cf6d4cf256d3c216c7733a6eae9\
                                c8557ca478a147db040def50e7955c1ab5819379


   HPKE-6-KE KE+PSK with default aad, external info, external hpke aad

   Ciphertext: \
   d8608444a1011818a1054cf38ab7422245935d23a66d8758212dbe21e54161712a49\
   1581fe3820e5aa386a07fc64a324fc692d455e7aa07bacea818353a2011834044d62\
   6f622d68706b655f365f6b65a12358383bc0cc314a33ffdb4e87eaf5d52d5ced617f\
   0896300c63bc25390bdcf5ff6b9f9cd4800f05864a1bae10c3b941205bd5b7b3afcb\
   1ba898c458308a745bf13677cf7ec0d2ac9a65e14bc5641ea9727d143a30f2535589\
                                1572f6958f5bc9898e33c5b926deb1f1ceba2da8


   HPKE-6-KE KE+PSK with external aad, external info, default hpke aad

   Ciphertext: \
   d8608444a1011818a1054c7913f581c059c8ec72f9ab5a58214e023cd8ca3239fd2d\
   9b29a580edd711e981551abd7751a004ff47057162b4a184818353a2011834044d62\
   6f622d68706b655f365f6b65a123583872af48d87d997690e3cfaa920dac46dc6095\
   216d05b58a5323d814ea5ee6f471b4fd99d996a9663ef0148aec8904acc6ea0ddda1\
   3c7315765830bf103402453fc9b6d846ad6f3a435aae99f628b7f323552e9136cfaf\
                                64a7a95de8e2656ad6b706c94e002f2410092c56


   HPKE-6-KE KE+PSK with external aad, external info, external hpke aad

   Ciphertext: \
   d8608444a1011818a1054c3b24712df521ce6daeb16d79582157122c22bb26402e9c\



Tschofenig, et al.      Expires 3 September 2026               [Page 66]

Internet-Draft                  COSE HPKE                     March 2026


   c64b46f817ec3b11d648f1de72499442efa7ffd13b07af1c818353a2011834044d62\
   6f622d68706b655f365f6b65a12358388cb8b6f65144bc3f730feb3c40dbbe759f8a\
   db2fc96a67552a431efdc7c5ec4ec78a415823e1422b532f35c7b8ee75619e46d6fc\
   9e4455a458308f628129208d995a3e5e7234680907ebcf15add2fa9579f910ad0e55\
                                b43e3faf5f8e8e41e1849d3e91a6ad8a5f07ef6e


   HPKE-7-KE COSE_Key: \
   a70102024d626f622d68706b655f375f6b650318352001215820235da0a3f782d1d6\
   3883301a1f465ce5ecb9ee21b5c956dc33af969716ac10122258200bd7226e1968f5\
   fca824b05749377e347ebab34dafb752941204ae153e18a7772358208c6710cca617\
                    4b6c57ab2f3166a3e12d18d5915201c98b4e48ddf65568f3a73a


   HPKE-7-KE KE+PSK with default aad, default info, default hpke aad

   Ciphertext: \
   d8608443a10103a10558201e7f005d9034fd70b784b478151f569c9e4116e8d9a6a8\
   71370be98fa1e2452d5821b51716881bdd056919af5fb588eefcb06200f220f48f50\
   0931bbbab04a82e03c3b818353a2011835044d626f622d68706b655f375f6b65a123\
   5841041479f005908668cb2492fb8cb8afcb9df4c0c89c11ccd18c2c3bc7fb42c931\
   2797245d5a3ab4eac0c0a87dc2cb0a2b8ce770c5757a44880257a48841639ca31e58\
   30e0ab73659cbbd3b6a43bcce5169a041599af3a8485e32d01264a0b134f11f9dcc9\
                                          7324b54127972b0fb93d9c11469602


   HPKE-7-KE KE+PSK with default aad, default info, external hpke aad

   Ciphertext: \
   d8608443a10103a1055820b1ffe35d48b498f0288ff46d6a61a4e90ff0befd1e1ec3\
   c94537b5f9af9920955821c23e3d1f53e82f94eeddd1588c5cadf50bfaf31f1d28d2\
   96c9047ba9727ee6b22d818353a2011835044d626f622d68706b655f375f6b65a123\
   58410424929f8f874446d29dcb78c37e6a5b50f1a4680e7a23d8f0014717645a90bd\
   a7b7f4bc6b920ea8ee042a644f6b1b5af8cd7e5fea40e424e3000b4c2532e3883d58\
   300bc1e619a7ff8f5b67c7e110e01f9e1018239c3c4bb3a1f63389453bdf3249b266\
                                          a321843aba2401d42804f627d5e457


   HPKE-7-KE KE+PSK with external aad, default info, default hpke aad

   Ciphertext: \
   d8608443a10103a105582064a16aad701de8efec4c898d53d75e273dab2ee7720d54\
   4700f3f26dc1e8b4aa58212cd39835cff3f3f303dd9dae20e79c789e0d425ee04112\
   f26962be476a94f0654f818353a2011835044d626f622d68706b655f375f6b65a123\
   5841047443a801c2579cc3a9683828ac1720d133dc0ea1d9c34b72dc3225aa1b203c\
   7eced7aafcca86dbda61dcc95efaacae431fe02626f390a7e97e4a8319c9d20c7f58\
   30cb47c1f7c40efdf049f874f9fe75ac7d1a494f2cf4882bfd492cc402822ab8f52a\
                                          51848f7e60e798dfb969c89bb44e61



Tschofenig, et al.      Expires 3 September 2026               [Page 67]

Internet-Draft                  COSE HPKE                     March 2026


   HPKE-7-KE KE+PSK with external aad, default info, external hpke aad

   Ciphertext: \
   d8608443a10103a1055820e413d828a5dfcfb33b686ba36a5d155327b096140f23e5\
   2b675731f2fa06ba3558213438a2918171fd8534f9e65fcc902f9cb117821f059b59\
   fdd76490a37a44aeaea8818353a2011835044d626f622d68706b655f375f6b65a123\
   5841047056fd1244388c2b611cde8e10585a66974fd59724cb6bdd82f8e576c6de06\
   dec1fec70238f7f0f83f13c58cad88bc38af95456427597d5314055cb67ef0380d58\
   308a5acd6f28e689c7b750291bf0a771863a0b38bb6e3d972522e0c4e96d2fac613f\
                                          c907615e4ec8df18f0923c2488e674


   HPKE-7-KE KE+PSK with default aad, external info, default hpke aad

   Ciphertext: \
   d8608443a10103a10558207e358aa4427767452becb89d519e0fa6896ae3c41019bf\
   5ec8ef6700fe248ad858216d1f77b27b44718c523d0fd25d532546678578e5b6ded4\
   f20a6a030367b673908d818353a2011835044d626f622d68706b655f375f6b65a123\
   5841042bb09d00627ab8c7ad3c224485f3b81a9a3f696f8c216b7543c37065860c86\
   5f9e18ab32654bcbb69e4a63797b838b6c040b24a6707a39f720486fa9f24c8e9658\
   30e2727f5ae33e384b37c80a9357dd2eedf9351b1422604d5883b1aeb4f32b227d1f\
                                          5d1c7328475ede37196bc2aaf6e131


   HPKE-7-KE KE+PSK with default aad, external info, external hpke aad

   Ciphertext: \
   d8608443a10103a1055820bbffb795e60de4a819c29f426c403685d125b32b67dadb\
   ba80218ffd00faa64658217b4d6953483445bd9a5dbf07d4fd2bea23e17806e02bbc\
   8e9a042ab73c7bbd9e82818353a2011835044d626f622d68706b655f375f6b65a123\
   5841045c1d347a472f3967d2c92324fd5dca6aa26df991a06de353e2b9eb4f4cccb4\
   2e098feadd4bd9f20f109a0c78e6a3c1d4af9a86e2243a68e331fd5352b993d7c758\
   3037d79f7df4f5d20aed2922e5a449125e977b209706b8e63bc194ec3d72a29e00bb\
                                          d0b7ab54fbb8e9619e2a57ebadce39


   HPKE-7-KE KE+PSK with external aad, external info, default hpke aad

   Ciphertext: \
   d8608443a10103a1055820a2d6dfc0464ecb11dcea7d68e5e6789f43a6361f5d59c3\
   7ed6f7bdf1e1a570b45821efc33ca5a6bc622204945b925063e7e9430792d637876b\
   b4f722238d9faa33fdd7818353a2011835044d626f622d68706b655f375f6b65a123\
   58410410a71911e9fff4710a3d2e9958a7514396351bd4782e1444e221c50e59d85b\
   e8831870513c71217d9047291de48f3b3ec0e92a4937ed32a7d5221a9e752f8b6f58\
   3023879441649cf5dbfc65318c6b844f250cac5b80f5c5bcc1c79549765c9ff79e54\
                                          f26f08aa83cce9ce80f24ed134ebf7





Tschofenig, et al.      Expires 3 September 2026               [Page 68]

Internet-Draft                  COSE HPKE                     March 2026


   HPKE-7-KE KE+PSK with external aad, external info, external hpke aad

   Ciphertext: \
   d8608443a10103a105582002a2da5a958beef87ad0ba08837b444a2f123187df56ee\
   2f102fdc26c1520788582124ad5a1dff05de46743fa4285a4c8296b9b402798ff585\
   617b99d71483a1e872c0818353a2011835044d626f622d68706b655f375f6b65a123\
   584104cda61f9062ce00aba834383c974eaa1f10f05515861073265508f5834c0980\
   d586f88cb101d7bcf8c39408bfac13004746c96ecb33974d98869b5be16d6cfb9358\
   30677210dede124a21c73b75d43d70597b512e6dd7b467bcd3f809347c039ebfab97\
                                          2c41db766608113bf178aeeef89b62


   HPKE-0 COSE_Key:: \
   a70102024e626f622d68706b655f302d696e7403182320012158201978838d5d7cec\
   cf63ef1b5206e7bf6e7878eda9fffef7f9372174559bb915b5225820ce11b8ec4906\
   471126f125f8309fa6d535b88bc2902659b2ec311f2210a0ecf1235820d584d0f00d\
                  9ac070e310e07af82af13f8f5ccf8c48feb74a9f5e9ac7e434d012


   HPKE-0 Encrypt0+PSK with default aad and default info

   Ciphertext: \
   d08344a1011823a2044e626f622d68706b655f302d696e742358410436497c25f707\
   c15c87f902d1e21c3cabb8d298511eb5a23aa5ca54846d296923539927ccb6e12c5d\
   2ea31e0322be9052881e1908463f74218759abaeb7acc8ee5821460f6df2872c7719\
                      0f2d109b40f9387738b161a11af42af43806afa23a2f43ea8c


   HPKE-0 Encrypt0+PSK with external aad and default info

   Ciphertext: \
   d08344a1011823a2044e626f622d68706b655f302d696e742358410408e74886e267\
   b409c5813e6ed9a5f8b142397b64d3266c03d124a4899265465d6d1c3d85e72ca170\
   c59f6748d6a314b81e065affa6c2a6a2b17d7f5e991a9f3258213fee4c1fb2daf759\
                      7130bf6777ff4c617e474ab4ae87df303f8c24575022f76f55


   HPKE-0 Encrypt0+PSK with default aad and external info

   Ciphertext: \
   d08344a1011823a2044e626f622d68706b655f302d696e7423584104d27a3f163efa\
   768558406af61bde46d8ddedf9ac6fbb21d737eabf5906c7f7f68f469b027d22d396\
   8692279cc4d45d937823486e0f3a118605778921b9e4d0775821d33af1cf7b36a32c\
                      21263ddf2257f85ace2257797fc9ce3b8362f7a71d7775c618


   HPKE-0 Encrypt0+PSK with external aad and external info




Tschofenig, et al.      Expires 3 September 2026               [Page 69]

Internet-Draft                  COSE HPKE                     March 2026


   Ciphertext: \
   d08344a1011823a2044e626f622d68706b655f302d696e7423584104a1dbd4acd8f6\
   9bc5e38f4bdaff6101aa8ecee2d637eee96f495174209a1e7fb27a934f3b17329a0f\
   b93c3cd76ceb339c6ea4bee4b950792c060ff686b50147135821c9ecd3b87eb93f19\
                      c7f220a9afbf7c3f0d8bc35766818c9f49148563ded4cd5de0


   HPKE-1 COSE_Key:: \
   a70102024e626f622d68706b655f312d696e740318252002215830a07787376d7be3\
   aefad3a37787f366fb5b9db711ea52da6007d6c0415edea639a3749f35e20b5db7fd\
   3f1acfa94fe88d22583093e13666684a788a3ddbdb3747923fccd850f072574b7a3f\
   bc4ce7bd810de7d0754ee5e0763061e3615ccac4a6231490235830a29d238c81ec58\
   17c4ad1b8f6e6f796ba76d6ed3bff6c730531c8469bf7e08c30e8645f690d6adc12a\
                                                          4411953082467a


   HPKE-1 Encrypt0+PSK with default aad and default info

   Ciphertext: \
   d08344a1011825a2044e626f622d68706b655f312d696e7423586104df5de432eca4\
   006ac093375950771fb12d1b61b1bc8498c2a04a4b0ea42130afb07fed7ae45e0de4\
   f51f872897440f16c06fe23c768f2663def46b6c5340261f45a8427d9da07e058e69\
   599b62e6712ed7e04704194900cd4f7a13e5d600b2e558212ed9d3916151acc3cc24\
                          7a6b5cfff03595f4bffb5e26d4a98ecdac227ffbd2d211


   HPKE-1 Encrypt0+PSK with external aad and default info

   Ciphertext: \
   d08344a1011825a2044e626f622d68706b655f312d696e7423586104a218f4c737e2\
   53d3b87094017731469274d9df3eb676192ad68e9fbad4523b51d1555b82e8780a79\
   49055188fe745234d1d75574f2b5ba944c5e3faab398d44477d579d7bdd6389e55f3\
   48d119eb9c022d465002381be0c3afb9674fbe016f4058217d4b45a3b68278465c57\
                          cc1b3acac76b9271213ff89dc7ee1208cbfa5d9ef47607


   HPKE-1 Encrypt0+PSK with default aad and external info

   Ciphertext: \
   d08344a1011825a2044e626f622d68706b655f312d696e7423586104d116a00b8ee8\
   24c1b6781c91d9fb4830928b963feacd9824c232f0f4f5b71a04a5e0be4149086381\
   32ab4c758db22f4c6e37bfe8d2903812cceef4c386e65529d102693f8c0c88ef9b94\
   8e06d9a6d6afdb29a8b781947af95b5ea00c99ca56ed582160e20429a820e789310f\
                          9af083fbf818141cf5a8ee186109f003941c3f05194d92


   HPKE-1 Encrypt0+PSK with external aad and external info




Tschofenig, et al.      Expires 3 September 2026               [Page 70]

Internet-Draft                  COSE HPKE                     March 2026


   Ciphertext: \
   d08344a1011825a2044e626f622d68706b655f312d696e74235861044aae7f5eb6ff\
   9aa01746b686d6d3fb70a899992c85387d81419ca412e3321863e89a3f758e8e0454\
   dadf8da49d510dcedea55f5bd4a21c05ac8d5adee32c3885b50592bdb10840840e16\
   9aa9617e53f919d03a9e4eee8ba9cedeea06296a59d75821ad5a3f69d0bc2502d480\
                          ba69622367278507ed68ff5c96ce5cfc742450e52cdb6a


   HPKE-2 COSE_Key:: \
   a70102024e626f622d68706b655f322d696e740318272003215842010ff539d3b9e6\
   fc491c324a1fccf71e4b3dca99c4ca3bbcdd715cb7732109b846f2c7a08b96fec81f\
   04a34c5fb694adb551a4f8e11cc336441378bd05471b79b70b22584200ebefdb1bff\
   b05f3eff770ec11b2b880a0a8f9f853297006e8db147b5e5cf34709e3ce71930d3c6\
   1ca1ddc7f33322323aa8dcec47748a503162aab814698f504a272358420164e63b64\
   4aeb24c393ba75243505a6f77f9c3acaf4f45925ec0d9a93f2838c46665449adae9d\
                  4f68fd02e504bc01032fff52c57281fd9f01dff04bc714d80a1b1f


   HPKE-2 Encrypt0+PSK with default aad and default info

   Ciphertext: \
   d08344a1011827a2044e626f622d68706b655f322d696e74235885040019b47bcd96\
   dddd5feb25b470146d1cf0c09f20d8e642468160835db40e29f25f2d25664afe2bbb\
   90daaebda1238ef5bb19ff321bde00da48764cd8a7270476e5e000fa4f7a92e769f7\
   aa71c06dda3397ef0f9a2b11e26571604d034b3c7c3ec07e0df4c6366377053e7230\
   efcb77cb123d40ad0e9513e54338c8d20443e4fc6aff2b27582115e3bbca19faa6f6\
                      1a7582db14aa58433d6876716c796e39b156e97fa4e0f5ecfd


   HPKE-2 Encrypt0+PSK with external aad and default info

   Ciphertext: \
   d08344a1011827a2044e626f622d68706b655f322d696e742358850401abc01f5afc\
   1dfbc2b40adf647f863bfa62c9ac2bc059e8678c3d1666acd150f4a0b7eb3a9b71e9\
   f5c617d89744ff529370d55a9ef4176b1265882611232e484d4701690e2e3dd1d184\
   b6e5cf202d1983d39e396f3ad776cd97f2760e1a570ca71f8ae29902a80c2f462eaf\
   da610ff9f03867fff20742816838efb536fd501f6ca10dc058213245639008b74fc5\
                      c71f37f3c302f94d54e95061dc14b86c59681d2b242c1d1de8


   HPKE-2 Encrypt0+PSK with default aad and external info

   Ciphertext: \
   d08344a1011827a2044e626f622d68706b655f322d696e742358850401b85a75afd2\
   d4832df126acb39630b1ecf97cfeba280bfbed6f0c3008daa590635740d7b4fdff28\
   070e2936a5b7bbb4772b897c548da2133133a6da63de96ef87a60013d6fb0195b5eb\
   9559b8f8d9a6fa12ae3bda7e3f7b75eef0e420c3fff312044c6a87a33e429408a8d0\
   7d27099cd4e1c0d1f61c38133b821ab1881a419a395f32d85821640e4aac586afbc9\



Tschofenig, et al.      Expires 3 September 2026               [Page 71]

Internet-Draft                  COSE HPKE                     March 2026


                      489818406f1f69bb30884cd01f5dbcf8bc8fc7ab6b26edebbb


   HPKE-2 Encrypt0+PSK with external aad and external info

   Ciphertext: \
   d08344a1011827a2044e626f622d68706b655f322d696e7423588504001f4e8064b1\
   74c08064fb07a48e73c92ec41073f74fd043a33cac2eb2b5a39679c15e20b8d228ce\
   93964a77f0766e460614114ac3beb2f6baec2675823821e81ef200e0b9c902e74524\
   1db2a85e3cf7717e2e61f8824a3fd8fb0d1403b367da7bb42fe63a2ed1ac4ce42aa2\
   9853d4a1dae37f4eef0a1193225d78811f1692943a81c5c15821188905cf7d36da69\
                      3355ba05457fd6039d5c1cd1f49185817d70e737b8da629978


   HPKE-3 COSE_Key:: \
   a60101024e626f622d68706b655f332d696e7403182920042158209f898a80cc4290\
   dfdf261d0a90571095afccd022b65f609fb7cbfc144b721539235820881c29bbf697\
                    0ef15bef05e2b6350ceed8cfcc77a7ce141e9a8ff99b0d998043


   HPKE-3 Encrypt0+PSK with default aad and default info

   Ciphertext: \
   d08344a1011829a2044e626f622d68706b655f332d696e742358202bf99fd198dfe5\
   0851ad960a2d593fe8ad32a9b84a304e7eaa3feef510609d105821322a3cb0425a6b\
                    9735ec81020f7a8f124de35b9c6788623bca0309d239677985b8


   HPKE-3 Encrypt0+PSK with external aad and default info

   Ciphertext: \
   d08344a1011829a2044e626f622d68706b655f332d696e742358205df8c7147ca3a6\
   5d94fffcacc61ed49a3790cad79534f31df74a91fb74b60f0c58219ed975688367df\
                    7f8264585cc25ea668cad87824b0b2eadd9984e530b904961c8a


   HPKE-3 Encrypt0+PSK with default aad and external info

   Ciphertext: \
   d08344a1011829a2044e626f622d68706b655f332d696e742358202a3900a4fbdd71\
   4b7624be04df2b031c63d9c9a852b788b0572da47b56a11b4e5821ac8087a1bbb462\
                    ccfa9b78f7c4e040e6041014ca783af8b754dddf52b72b0ca3f1


   HPKE-3 Encrypt0+PSK with external aad and external info

   Ciphertext: \
   d08344a1011829a2044e626f622d68706b655f332d696e742358208bed4488608e6e\



Tschofenig, et al.      Expires 3 September 2026               [Page 72]

Internet-Draft                  COSE HPKE                     March 2026


   a3e3b10e33d7cb35d106a378e56ceddb9b421201254516285b58214a1304836a432f\
                    c64fbfd0f445ae464a686c950e0fefc6ca1d6cef99b9ad8a7865


   HPKE-4 COSE_Key:: \
   a60101024e626f622d68706b655f342d696e7403182a200421582098f335c76496e8\
   1d70b464b7168ca9331ca28bf6077db774fb8a652a98466151235820e06b4e6d7d1e\
                    7c5feabc632c61cfb7761163608b5d5e1c82a1d9ffbc4b449f4c


   HPKE-4 Encrypt0+PSK with default aad and default info

   Ciphertext: \
   d08344a101182aa2044e626f622d68706b655f342d696e74235820773768059571f7\
   487c63dbbb6684932a13f8782a8865a721c1f91899efb91958582109794195e1ccbc\
                    f3a4091254df0b980e3dc2a4f76a16f91d10106bccd4e17ec0b1


   HPKE-4 Encrypt0+PSK with external aad and default info

   Ciphertext: \
   d08344a101182aa2044e626f622d68706b655f342d696e742358204972c7ccf0072b\
   fcca44cd334b6170895e59bc08ac24598b9dc024c8537ba234582185c48849033c56\
                    2fe8cd0fb110b96546b1f9fb0a956462b8803501a0f342b36f1b


   HPKE-4 Encrypt0+PSK with default aad and external info

   Ciphertext: \
   d08344a101182aa2044e626f622d68706b655f342d696e74235820edeabe2d694177\
   e36bd06120e11c45a1d78f64336c5a9ef6f3a09f5adfc42b0b582188d2a43d93aacc\
                    89bd29e3efd7be8b56d8d3c02b3be1da7f5ce8b55f4b93190334


   HPKE-4 Encrypt0+PSK with external aad and external info

   Ciphertext: \
   d08344a101182aa2044e626f622d68706b655f342d696e74235820a4bcb538ad59e8\
   6e0e1cf8b615eee457eee2ce659c88fb263fc9d064a3022f145821ded166fc8867b6\
                    b45628630ee777df2e47a03a81f00c961c1443d225182b01b835


   HPKE-5 COSE_Key:: \
   a60101024e626f622d68706b655f352d696e7403182b20052158388a68a40d28b469\
   ca93ef6ab8f4095e0c467ed7da367ec674ea966d23773dfc3ad39765409f9c9f1c34\
   900c355777a9a76ddbf3e2e06e0141235838e86c18e103423df47ed171fc82f8d398\
   adfb61bebc17ed35eb85246bfba090e46841dadedf5f1049433ed3a875882a934fb7\
                                                            07588a2d12d5



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   HPKE-5 Encrypt0+PSK with default aad and default info

   Ciphertext: \
   d08344a101182ba2044e626f622d68706b655f352d696e742358386925a3a6a036a2\
   d76e66ca435f712055a771c3d2b744e8b8e0ad01534ac236b1d8c3b7741876e7a92f\
   8646f3b7cefc4236914698fe93c7785821965d22abb1540da8024724d12a8fd848e7\
                                        9e2b9cd2f74c44e0e85166853e98b1d8


   HPKE-5 Encrypt0+PSK with external aad and default info

   Ciphertext: \
   d08344a101182ba2044e626f622d68706b655f352d696e742358387b8c8969d60d6f\
   a9668453cf4dd9e73d769a362a0892e754ee091ed7de93964648795a35613eda69a4\
   b164d43abee4560c7c3604fa9dafcc5821c82bea6fd7f13c29f3a4931159eb8caf52\
                                        9cbafdd677c2354ed5e6accf84a55999


   HPKE-5 Encrypt0+PSK with default aad and external info

   Ciphertext: \
   d08344a101182ba2044e626f622d68706b655f352d696e742358389a4882d84ca735\
   9da36adf7a80a72feaed07e32014aacabdebea553868f3482b15cc42c573c6185f3b\
   a4744d22df70ad99b74e68702944a858210a23b921a2a884507b661239bd79302701\
                                        f3a5b479f97f3260681b9d4185da5920


   HPKE-5 Encrypt0+PSK with external aad and external info

   Ciphertext: \
   d08344a101182ba2044e626f622d68706b655f352d696e74235838bdfc9d7a69532d\
   605cd20c454713f2bba183566e7d5814535e4648b239fb2a1845e8030718ff0243de\
   3d854d25dc0cb3fc87fc692224c79558213c73d2bcf43ec29f3a91306567d2903532\
                                        b03e4224948d702e5be80ee9e9644f9d


   HPKE-6 COSE_Key:: \
   a60101024e626f622d68706b655f362d696e7403182c2005215838958b1eb8523293\
   b880d8744265760378b4f9a72f9ab31c9147205207bfcc114186347f030f3fd894d7\
   a5b9e385154141d6e5c41e06e977032358387063a27888d7919aff93704896ec21a4\
   d36312d5a101fac8f75183603fbd718b5aa68a33eeaa5c8ac1d4e400c938976c6e0d\
                                                            a5080f2e33ad


   HPKE-6 Encrypt0+PSK with default aad and default info

   Ciphertext: \
   d08344a101182ca2044e626f622d68706b655f362d696e74235838e5b4599601b2bb\



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   a65b4eccd053a4163c70ba55c47b6b2cdbcbd7da4301ba954aa2e106e342acf4557a\
   68ef1d9fed298ce10a5489fb01006f5821aab8bdac5bb7e89199c16293caa5ce057a\
                                        0a03de3b643d885665866fdf9548b6b2


   HPKE-6 Encrypt0+PSK with external aad and default info

   Ciphertext: \
   d08344a101182ca2044e626f622d68706b655f362d696e74235838535c3766b98650\
   daeef42882dfe251e4502faa645a315fad0eaf0daa08c68366cf281b3a0e0924fc87\
   f83d8e6462cd039907b9ee7fccbadd5821d10bfa98fbff244a4a7ff6940bad877fad\
                                        8e7bab901a503a51b365f50ee6baaada


   HPKE-6 Encrypt0+PSK with default aad and external info

   Ciphertext: \
   d08344a101182ca2044e626f622d68706b655f362d696e742358387b1e949b71d32c\
   02236d08f29afebc7f12c14e5e21e5909683ee9ce2cb804b42d6134a88290a38f92f\
   163934329c01d70b855aa0127f660658214860e64ac9613b9188fbe659a89fde3fbb\
                                        f87e05d828bed3112e039ee1060c5914


   HPKE-6 Encrypt0+PSK with external aad and external info

   Ciphertext: \
   d08344a101182ca2044e626f622d68706b655f362d696e74235838f8133adda20c17\
   be5cce697b83cd305a9304f596f663440a2547cdd86afc4ec3b061b8ab18e886bfdc\
   aad18164f35da4337dad314e63ba5a58216023c82c3ae28723cc8396d523d6946948\
                                        1b67edbfaca4df0a6bde5f472398716b


   HPKE-7 COSE_Key:: \
   a70102024e626f622d68706b655f372d696e7403182d2001215820a60f63d47f6e4a\
   9010c65140f827f05cd04bc45ba2f75e8d9aee0ebb6d519ffe225820b1e33d1b7202\
   11dcbb7b58694fd45bad75f494656ffa754505d80044c1d1f5fd235820cff95cf1ce\
                  5c67edcb20881bc02829d870f5f50cdaa03d1e1522c67505b6d5f4


   HPKE-7 Encrypt0+PSK with default aad and default info

   Ciphertext: \
   d08344a101182da2044e626f622d68706b655f372d696e7423584104df99cbe182c0\
   41a6502415fdedfc22b90bfcd33879dc9bc9e30b9ddc74b3a837acc71f09ad252180\
   bd01da4df7b7487701ef6a80b35738e9c1f37cf40675bc4b58213da7027ac0e3943f\
                      df967e75bac20fd621d1726220813b416361c95e32557b4dbc





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   HPKE-7 Encrypt0+PSK with external aad and default info

   Ciphertext: \
   d08344a101182da2044e626f622d68706b655f372d696e74235841041cb6cdbeb778\
   329f4812be9da0169ac0510646a5b7d63d7ca845241c8d6200d9489be511fdc12892\
   0a3bc0998312dc0db82b314fbb2e046c7bc20ff5afe767f7582112b9b197cabfd884\
                      55936d8037908bffe7b07c2953bec1c0b3b963c9fc74a8716d


   HPKE-7 Encrypt0+PSK with default aad and external info

   Ciphertext: \
   d08344a101182da2044e626f622d68706b655f372d696e7423584104467cc0f1d194\
   ea0dde9dc946d67ef89b7bb4026617bf68cef65d8127077a5209334a057e2674d213\
   3278d729595fd51a1556ee8f9df91acdae106671bdbaf2885821d2786254e1311ca4\
                      f884717a60d1b493b98cfe44be88d2820c7585e57cdcb2c8be


   HPKE-7 Encrypt0+PSK with external aad and external info

   Ciphertext: \
   d08344a101182da2044e626f622d68706b655f372d696e7423584104f62055c9d997\
   d492879363ee13e4cdf676172c7cdf24d27e18befab5886fe93228306646f05a06c7\
   ac2d807301ea997374a3aee90b4c12c8dca348ea93fae5425821e831f27b7d99e448\
                      97f409648e54594cc5f3ff1fb184979d97a5af5799b6c0ca64

Authors' Addresses

   Hannes Tschofenig
   University of Applied Sciences Bonn-Rhein-Sieg
   Germany
   Email: hannes.tschofenig@gmx.net


   Orie Steele (editor)
   Tradeverifyd
   United States
   Email: orie@or13.io


   Daisuke Ajitomi
   bibital
   Japan
   Email: dajiaji@gmail.com







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   Laurence Lundblade
   Security Theory LLC
   United States
   Email: lgl@securitytheory.com


   Michael B. Jones
   Self-Issued Consulting
   United States
   Email: michael_b_jones@hotmail.com
   URI:   https://self-issued.info/








































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