Description
Tugtainer is a self-hosted app for automating updates of Docker containers. Prior to version 1.31.3, when the OIDC login flow completes, backend/modules/auth/providers/auth_oidc_provider.py decodes the id_token returned by the identity provider's token endpoint using jose.jwt.get_unverified_claims() instead of jwt.decode(). This skips signature verification, audience (aud) validation, issuer (iss) validation, and expiry (exp) checking entirely. The extracted claims (email/sub/preferred_username) are then used directly as the user_id for the resulting Tugtainer session. This issue has been patched in version 1.31.3.
References4
Metrics
- CVSS 3.1
-
8.1
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 27 · as of 10 November 2026
- CWE
- CWE-347
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