Description
A flaw was found in the SAML adapter component of Keycloak, which is used to secure applications with SAML-based authentication. The adapter fails to verify that the issuer of a signed SAML assertion matches the expected identity provider configured for the application. If multiple identity providers share the same trusted signing key, an attacker who controls one of those providers can create a validly signed assertion to log into the application as any user, potentially gaining full administrative control.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Red Hat | Red Hat build of Keycloak 26.4 | — | — |
| Red Hat | Red Hat build of Keycloak 26.4.17 | — | — |
| Red Hat | Red Hat build of Keycloak 26.6 | — | — |
| Red Hat | Red Hat build of Keycloak 26.6.8 | — | — |
| Red Hat | Red Hat AMQ Broker 7 | — | — |
| Red Hat | Red Hat Fuse 7 | — | — |
| Red Hat | Red Hat JBoss Enterprise Application Platform 7 | — | — |
| Red Hat | Red Hat JBoss Enterprise Application Platform 8 | — | — |
| Red Hat | Red Hat JBoss Enterprise Application Platform Expansion Pack | — | — |
| Red Hat | Red Hat Satellite 6 | — | — |
| Red Hat | Red Hat Single Sign-On 7 | — | — |
Advisories 1
- WID-SEC-2026-4375 Keycloak: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 11, 2026
References
- RHSA-2026:95759 vendor-advisory
- RHSA-2026:95760 vendor-advisory
- RHSA-2026:95761 vendor-advisory
- RHSA-2026:95762 vendor-advisory
- https://access.redhat.com/security/cve/CVE-2026-93998 vdb-entry
- RHBZ#2537164 issue-tracking