Authlib: ID token can disable its own nonce validation via the nonce_supported claim (authlib authlib)

CVE-2026-114617
MEDIUM 4.2

En bref

Source
NVD
EPSS
EPSS 0.27 % · centile 19 ()
État
PUBLISHED
Publiée
Mise à jour
Attribuée par
GitHub_M
Statut NVD
Analyzed

Description

Authlib is a Python library which builds OAuth and OpenID Connect servers. Prior to 1.9.0, OpenIDMixin.parse_id_token() reads the nonce_supported decision from the untrusted ID token being validated and sets the expected nonce to null when that claim is the JSON boolean false. In implicit and hybrid relying parties, or applications that directly accept externally supplied ID tokens, an attacker with a captured validly signed token can bypass the nonce-to-session binding and replay the victim's token into an attacker-controlled session. Plain authorization code flow is not affected, and the token must still pass signature, issuer, and audience validation. OpenIDMixin.parse_id_token() trusts nonce_supported in both authlib/integrations/base_client/sync_openid.py and authlib/integrations/base_client/async_openid.py to disable the expected nonce. This issue is fixed in version 1.9.0.

Faiblesses (CWE)

  • CWE-294 — Contournement d'authentification par capture et rejeu
  • CWE-807 — Reliance on Untrusted Inputs in a Security Decision

Références

Scores

VersionScoreVecteurÉvalué par
CVSS 3.1MEDIUM 4.2CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:NGitHub_M
CVSS 3.1MEDIUM 4.2CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:NNVD · security-advisories@github.com (Secondary)

Avis

Références européennes

Configurations affectées (CPE NVD)

Produits affectés

ProduitVersions
authlib · authlibaffected < 1.9.0

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD