Vulnerability in Red Hat Build of Keycloak

[ Description ]Official description

A flaw was found in the Dynamic Client Registration flow of the Keycloak identity and access management server. The issue occurs because the registration process fails to filter security-sensitive client attributes when a new client is created. An attacker with a valid Initial Access Token can register a client that bypasses audience checks during token introspection. This allows the attacker to view sensitive identity information, roles, and session details from access tokens belonging to other applications in the same realm.

[ Fixes ]Fixes and patches

No fix or interim patch is linked from our sources yet. Check the vendor references below and limit exposure of affected systems until a fix is available.

[ Advisories ]Government CERT advisories

• BSI CERT-Bund4 Oct 2026WID-SEC-2026-3727

  Keycloak: Multiple vulnerabilities Translated from German

  CVE-2026-105302CVE-2026-105301CVE-2026-105306

[ References ]References

• access.redhat.com/security/cve/CVE-2026-105306
• bugzilla.redhat.com/show_bug.cgi