## Authlib: empty signatures validation in JWS JSON deserialization

- 種別: advisory
- 重大度: critical
- 関連技術: python
- CVE: CVE-2026-96760
- 公開日時: 2026-10-27T14:50:18.000Z
- 情報源: GitHub Advisory Database (https://github.com/advisories/GHSA-6v38-4h7w-rj9h)
- パーマリンク: https://vulnpulse.app/items/ghsa-ghsa-6v38-4h7w-rj9h

影響: pip:authlib <= 1.8.0 → 1.9.0
Authlib (prior to 1.9.0) contains a signature verification bypass vulnerability. The JsonWebSignature.deserialize_json() method accepts a JSON Serialization JWS object and returns the payload as successfully verified without checking for a signature and without requiring a cryptographic key. Root cause authlib/jose/rfc7515/jws.py, read on the installed 1.8.0 artifact: python is_valid = True # set before anything is checked for header_obj in obj["signatures"]: # empty array means the body never…