A flaw was found in Keycloak. An authenticated administrator with the `manage-clients` role can exploit a Time-of-check to time-of-use (TOCTOU) vulnerability in the name-based admin role checks. This allows the attacker to escalate their privileges to `realm-admin` for all users within the realm, granting them extensive control over the system. The composite role relationship persists even after the attacker's own permissions are revoked and across system reboots.
Credits
Red Hat would like to thank Daniel Peters (Operating Intelligence Inc.), Lior Moshe (Operating Intelligence Inc.), and Uri Rolls (Operating Intelligence Inc.) for reporting this issue.
