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.

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History

Thu, 28 May 2026 04:45:00 +0000

Type Values Removed Values Added
Description 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.
Title Keycloak: keycloak: privilege escalation via time-of-check to time-of-use (toctou) vulnerability
First Time appeared Redhat
Redhat build Keycloak
Weaknesses CWE-367
CPEs cpe:/a:redhat:build_keycloak:
Vendors & Products Redhat
Redhat build Keycloak
References
Metrics cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N'}


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cve-icon MITRE

Status: PUBLISHED

Assigner: redhat

Published:

Updated: 2026-05-28T04:27:08.794Z

Reserved: 2026-05-28T03:31:58.205Z

Link: CVE-2026-9796

cve-icon Vulnrichment

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cve-icon NVD

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cve-icon Redhat

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cve-icon OpenCVE Enrichment

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Weaknesses