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 hol…
Published: 2026-09-03 · CVSS: 9.3 · CVSS 4.0
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 restricted. This is an incomplete fix for CVE-2024-33663.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7