Published: October 23, 2026 | Last Modified: October 23, 2026
The Goobi viewer is a web application that allows digitised material to be displayed in a web browser. From version 25.01 to before version 26.05, AuthenticationEndpoint.verifyOpenIdToken builds its verifier as JWT.require(algorithm).withIssuer(issuer).build() and does not enforce the aud claim during cryptographic validation. The aud check is performed manually afterwards via a single string-equality call, which only handles single-string aud values. In a multi-RP IdP setup, a token whose single-string aud matches the viewer's client ID but was issued for a different relying party passes the check and authenticates the attacker as the token's sub. This issue has been patched in version 26.05.
This analysis is generated by Ghostwire from NVD, CISA KEV, EPSS, and open-source intelligence data. Verify findings through primary sources before acting.