Authlib: empty signatures validation in JWS JSON deserialization

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…

Read on GitHub Advisory Database

On 10/27/2026, 11:50 PM, GitHub Advisory Database published "Authlib: empty signatures validation in JWS JSON deserialization" (type: Advisory). Severity is "Critical" (critical). Related technologies: Python. CVE: CVE-2026-96760.