Tinyauth: >> Tinyauth Security Vulnerabilities
Tinyauth is an authentication and authorization server. Prior to 5.0.3, the OIDC token endpoint does not verify that the client exchanging an authorization code is the same client the code was issued to. A malicious OIDC client operator can exchange another client's authorization code using their own client credentials, obtaining tokens for users who never authorized their application. This violates RFC 6749 Section 4.1.3. This vulnerability is fixed in 5.0.3.
CVSS Score
6.5
EPSS Score
0.0
Published
2026-03-12
Tinyauth is an authentication and authorization server. Prior to 5.0.3, the OIDC authorization endpoint allows users with a TOTP-pending session (password verified, TOTP not yet completed) to obtain authorization codes. An attacker who knows a user's password but not their TOTP secret can obtain valid OIDC tokens, completely bypassing the second factor. This vulnerability is fixed in 5.0.3.
CVSS Score
8.5
EPSS Score
0.001
Published
2026-03-12