CVE-2026-9796: Red Hat Build Of Keycloak

Medium severity, CVSS 6.5. EPSS: 0.4% chance of exploitation in the next 30 days.

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.

Affected products

• Red Hat Build Of Keycloak: affected versions not specified

Published 2026-05-28. Last modified 2026-09-15.