CVE-2026-55459: Goobi viewer: OpenID JWT audience not enforced by the verifier

Vulnerability summary

CVE-2026-55459 is a high (CVSS 7.4) Improper Authentication vulnerability in intranda goobi-viewer-core.

Timeline

1. 23-10-2026
   PublishedVulnerability first disclosed.
2. 23-10-2026
   Last modifiedVulnerability information updated.

Description

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.

• CWE-287Improper AuthenticationWhen an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.
• CWE-345Insufficient Verification of Data AuthenticityThe product does not sufficiently verify the origin or authenticity of data, in a way that causes it to accept invalid data.