CVE-2026-85394 (GCVE-0-2026-85394)
Vulnerability from cvelistv5
Published
2026-09-03 18:54
Modified
2026-09-14 13:50
Severity ?
9.3 (Critical) - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
9.1 (Critical) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
CWE
  • CWE-347 - Improper Verification of Cryptographic Signature
Summary
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.
References
Impacted products
Vendor Product Version
mpdavis python-jose Version: 0   ≤ 3.5.0
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