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CVE-2026-85394 (GCVE-0-2026-85394)

Vulnerability from cvelistv5 – Published: 2026-09-03 18:54 – Updated: 2026-09-03 18:54
VLAI
Title
python-jose through 3.5.0 Algorithm Confusion via DER-encoded Public Key as HMAC Secret
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.
CWE
  • CWE-347 - Improper Verification of Cryptographic Signature
Impacted products
Vendor Product Version CPE status
mpdavis python-jose Affected: 0 , ≤ 3.5.0 (semver)
    cpe:2.3:a:python-jose_project:python-jose:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-07-06 00:00
Show details on NVD website

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
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