CVE-2026-2603: Keycloak: Unauthorized authentication via disabled SAML Identity Provider
(updated )
A flaw was found in Keycloak. A remote attacker could bypass security controls by sending a valid SAML response from an external Identity Provider (IdP) to the Keycloak SAML endpoint for IdP-initiated broker logins. This allows the attacker to complete broker logins even when the SAML Identity Provider is disabled, leading to unauthorized authentication.
References
- access.redhat.com/errata/RHSA-2026:3925
- access.redhat.com/errata/RHSA-2026:3926
- access.redhat.com/errata/RHSA-2026:3947
- access.redhat.com/errata/RHSA-2026:3948
- access.redhat.com/security/cve/CVE-2026-2603
- bugzilla.redhat.com/show_bug.cgi?id=2440300
- github.com/advisories/GHSA-x4p7-7chp-64hq
- github.com/keycloak/keycloak/commit/4fd5367e6cc28cfa68fb2240fc459c12b1fdbf2a
- github.com/keycloak/keycloak/commit/8ed7e59dc08d79751a27c23aadb590f06b43f132
- github.com/keycloak/keycloak/commits/26.5.5
- github.com/keycloak/keycloak/issues/46911
- github.com/keycloak/keycloak/pull/46932
- nvd.nist.gov/vuln/detail/CVE-2026-2603
Code Behaviors & Features
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