CVE-2026-107724

The fast-jwt library (version 6.2.4 ) contains a vulnerability where raw serialized public JWK or JWKS JSON can be incorrectly classified as an HMAC secret . The root cause is located in src/crypto.js within the performDetectPublicKeyAlgorithms function, which treats non-PEM strings as symmetric ...

CVE-2026-107724 fast-jwt treats raw public JWK JSON as an HMAC secret, enabling HS256 token forgery

fast-jwt provides fast JSON Web Token JWT implementation. In 6.2.4, fast-jwt can classify raw serialized public JWK or JWKS JSON as an HMAC secret because src/crypto.js performDetectPublicKeyAlgorithms treats non-PEM strings as symmetric key material. If HS256 is explicitly allowed or inferred, a...

CVE-2026-85394 python-jose through 3.5.0 Algorithm Confusion via DER-encoded Public Key as HMAC Secret

python-jose through 3.5.0 fails to properly validate asymmetric keys in HMAC initialization, accepting DER-encoded public keys that lack PEM armor or SSH prefixes. Attackers holding the service's public key can forge HS256 tokens that pass verification when algorithms are not explicitly restricte...