Authlib: JWS/JWT accepts unknown crit headers (RFC violation → possible authz bypass) (authlib authlib)
En bref
- Source
- NVD
- EPSS
- EPSS 0.26 % · centile 18 ()
- État
- PUBLISHED
- Publiée
- Mise à jour
- Attribuée par
- GitHub_M
- Statut NVD
- Modified
Rechercher sur…
Description
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.
Faiblesses (CWE)
Références
Scores
| Version | Score | Vecteur | Évalué par |
|---|---|---|---|
| CVSS 3.1 | HIGH 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N | GitHub_M |
| CVSS 3.1 | HIGH 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N | NVD · security-advisories@github.com (Secondary) |
Avis
- GHSA-9ggr-2464-2j32 — Authlib: JWS/JWT accepts unknown crit headers (RFC violation → possible authz bypass)
- PYSEC-2026-1200 — Authlib: JWS/JWT accepts unknown crit headers (RFC violation → possible authz bypass)
Références européennes
- ENISA EUVD · EUVD-2025-30790
- GCVE · GCVE-0-2025-59420
Configurations affectées (CPE NVD)
cpe:2.3:a:authlib:authlib:*:*:*:*:*:*:*:*< 1.6.4
Produits affectés
| Produit | Versions |
|---|---|
| authlib · authlib | affected < 1.6.4 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |