RFC 9449 - OAuth 2.0 Demonstrating Proof of Possession (DPoP)

Category: Standards Track
ISSN: 2070-1721
Authors: D. Fett (Authlete), B. Campbell (Ping Identity), J. Bradley (Yubico), T. Lodderstedt (Tuconic), M. Jones (Self-Issued Consulting), D. Waite (Ping Identity)
Date: September 2023

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Abstract

This document describes a mechanism for sender-constraining OAuth 2.0 tokens via a proof-of-possession mechanism on the application level. This mechanism allows for the detection of replay attacks with access and refresh tokens.

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Status of This Memo

This is an Internet Standards Track document.

This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in Section 2 of RFC 7841.

Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at https://www.rfc-editor.org/info/rfc9449.

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Copyright Notice

Copyright (c) 2023 IETF Trust and the persons identified as the document authors. All rights reserved.

This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Revised BSD License.

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Contents

• 1. Introduction
  • 1.1. Conventions and Terminology
• 2. Objectives
• 3. Concept
• 4. DPoP Proof JWTs
  • 4.1. The DPoP HTTP Header
  • 4.2. DPoP Proof JWT Syntax
  • 4.3. Checking DPoP Proofs
• 5. DPoP Access Token Request
  • 5.1. Authorization Server Metadata
  • 5.2. Client Registration Metadata
• 6. Public Key Confirmation
  • 6.1. JWK Thumbprint Confirmation Method
  • 6.2. JWK Thumbprint Confirmation Method in Token Introspection
• 7. Protected Resource Access
  • 7.1. The DPoP Authentication Scheme
  • 7.2. Compatibility with the Bearer Authentication Scheme
  • 7.3. Client Considerations
• 8. Authorization Server-Provided Nonce
  • 8.1. Nonce Syntax
  • 8.2. Providing a New Nonce Value
• 9. Resource Server-Provided Nonce
• 10. Authorization Code Binding to a DPoP Key
  • 10.1. DPoP with Pushed Authorization Requests
• 11. Security Considerations
  • 11.1. DPoP Proof Replay
  • 11.2. DPoP Proof Pre-generation
  • 11.3. DPoP Nonce Downgrade
  • 11.4. Untrusted Code in the Client Context
  • 11.5. Signed JWT Swapping
  • 11.6. Signature Algorithms
  • 11.7. Request Integrity
  • 11.8. Access Token and Public Key Binding
  • 11.9. Authorization Code and Public Key Binding
  • 11.10. Hash Algorithm Agility
  • 11.11. Binding to Client Identity
• 12. IANA Considerations
  • 12.1. OAuth Access Token Types Registration
  • 12.2. OAuth Extensions Error Registration
  • 12.3. OAuth Parameters Registration
  • 12.4. HTTP Authentication Schemes Registration
  • 12.5. Media Type Registration
  • 12.6. JWT Confirmation Methods Registration
  • 12.7. JSON Web Token Claims Registration
  • 12.8. Hypertext Transfer Protocol (HTTP) Field Name Registration
  • 12.9. OAuth Authorization Server Metadata Registration
  • 12.10. OAuth Dynamic Client Registration Metadata
• 13. References
  • 13.1. Normative References
  • 13.2. Informative References
• Acknowledgements
• Authors' Addresses

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Related Resources

• Official Text: RFC 9449 (TXT)
• Official Page: RFC 9449 DataTracker
• Info: RFC Editor Info