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?
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 ?
5.1 (Medium)
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
CWE
  • CWE-358 - Improperly Implemented Security Check for Standard
Assigner
References
Impacted products
Vendor Product Version
OpenIDC liboauth2 Affected: 0 , < 2.3.0 (semver)
Create a notification for this product.
Credits
Michał Majchrowicz (AFINE Team) Marcin Wyczechowski (AFINE Team)
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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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