Description (CNA)
Authlib is a Python library which builds OAuth and OpenID Connect servers. Prior to version 1.6.4, Authlib’s JWS verification accepts tokens that declare unknown critical header parameters (crit), violating RFC 7515 “must‑understand” semantics. An attacker can craft a signed token with a critical header (for example, bork or cnf) that strict verifiers reject but Authlib accepts. In mixed‑language fleets, this enables split‑brain verification and can lead to policy bypass, replay, or privilege escalation. This issue has been patched in version 1.6.4.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| authlib / authlib | affected < 1.6.4 |
CWE
CWE-345, CWE-863
References
- https://github.com/authlib/authlib/security/advisories/GHSA-9ggr-2464-2j32
- https://github.com/authlib/authlib/commit/6b1813e4392eb7c168c276099ff7783b176479df
ADP enrichment
No English description supplied.
No references supplied.
No English description supplied.