CVE-2026-54431

In liboauth2 the Demonstrating Proof-of-Possession (DPoP) verifier accepts a proof whose JSON Web Key (jwk) header contains private key material. RFC 9449 section 4.3 step 7 requires the verifier to reject such a proof but oauth2_token_verify() function returns success for a malformed DPoP proof that embeds the private Elliptic Curve (EC) key in the header. This issue was fixed in version 2.3.0

CVSS

No CVSS.

References

Link	Resource
https://cert.pl/en/posts/2026/07/CVE-2026-54430
https://github.com/OpenIDC/liboauth2
https://github.com/OpenIDC/liboauth2/commit/c0b57152ed6a0af33aeb04a60bd7f5bff5ab8800

Configurations

No configuration.

History

02 Jul 2026, 12:17

Type	Values Removed	Values Added
References	~~{'url': 'https://cert.pl/en/posts/2026/06/CVE-2026-54430', 'source': 'cvd@cert.pl'}~~	() https://cert.pl/en/posts/2026/07/CVE-2026-54430 -

02 Jul 2026, 11:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-02 11:16

Updated : 2026-07-02 17:43

NVD link : CVE-2026-54431

Mitre link : CVE-2026-54431

CVE.ORG link : CVE-2026-54431

JSON object : View

Products Affected

No product.

CWE

CWE-358

Improperly Implemented Security Check for Standard

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