Security Advisory
CVE-2026-54431
N/A
UNKNOWN
Vulnerability Description
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
Published Date
July 2, 2026
Official Source
NIST NVD Advisory