CVE-2026-54431 (GCVE-0-2026-54431)
Vulnerability from cvelistv5 – Published: 2026-07-02 10:30 – Updated: 2026-07-02 12:16 X_Open Source
VLAI
EPSS
VEX
Title
Improper Data Validation in liboauth2
Summary
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
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-02 12:16 UTC
CWE
- CWE-358 - Improperly Implemented Security Check for Standard
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://cert.pl/en/posts/2026/07/CVE-2026-54430 | third-party-advisory |
| https://github.com/OpenIDC/liboauth2 | product |
| https://github.com/OpenIDC/liboauth2/commit/c0b57… | issue-tracking |
Impacted products
Date Public
2026-07-02 00:00
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