Copyright © 2012 Red Hat, Inc. All rights reserved. Moderate 2026-05-28T03:32:50 keycloak: Keycloak: Privilege escalation via Time-of-Check to Time-of-Use (TOCTOU) vulnerability 6.5 CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N CWE-367

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.

A Moderate privilege escalation flaw exists in Keycloak where an authenticated administrator with `manage-clients` privileges can exploit a Time-of-Check to Time-of-Use (TOCTOU) vulnerability. This allows them to escalate their privileges to `realm-admin` for all users within the realm, impacting the integrity of role-based access control. 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. Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability. Red Hat Build of Keycloak Affected rhbk/keycloak-rhel9 https://www.cve.org/CVERecord?id=CVE-2026-9796 https://nvd.nist.gov/vuln/detail/CVE-2026-9796