CVE-2026-85394
CriticalCVSS 9.1Summary
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.
Risk Assessment
An attacker could impersonate any user or gain unauthorized access to resources protected by JWT tokens.
Recommendation
Update python-jose to a fully patched version or explicitly restrict algorithms used for token verification.
Other vulnerabilities in python-jose
Original NVD description (English source)
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.