A flaw was found in Keycloak. An authenticated user with the uma_protection role can bypass User-Managed Access (UMA) policy validation. This allows the attacker to include resource identifiers owned by other users in a policy creation request, even if the URL path specifies an attacker-owned resource. Consequently, the attacker gains unauthorized permissions to victim-owned resources, enabling them to obtain a Requesting Party Token (RPT) and access sensitive information or perform unauthorized actions.
History

Thu, 02 Apr 2026 14:15:00 +0000

Type Values Removed Values Added
CPEs cpe:/a:redhat:build_keycloak: cpe:/a:redhat:build_keycloak:26.4::el9
References
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Thu, 02 Apr 2026 13:15:00 +0000

Type Values Removed Values Added
Description A flaw was found in Keycloak. An authenticated user with the uma_protection role can bypass User-Managed Access (UMA) policy validation. This allows the attacker to include resource identifiers owned by other users in a policy creation request, even if the URL path specifies an attacker-owned resource. Consequently, the attacker gains unauthorized permissions to victim-owned resources, enabling them to obtain a Requesting Party Token (RPT) and access sensitive information or perform unauthorized actions.
Title Keycloak: keycloak: uma policy bypass allows authenticated users to gain unauthorized access to victim-owned resources.
First Time appeared Redhat
Redhat build Keycloak
Weaknesses CWE-551
CPEs cpe:/a:redhat:build_keycloak:
Vendors & Products Redhat
Redhat build Keycloak
References
Metrics cvssV3_1

{'score': 8.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: redhat

Published:

Updated: 2026-04-02T16:35:04.681Z

Reserved: 2026-03-23T08:51:40.787Z

Link: CVE-2026-4636

cve-icon Vulnrichment

Updated: 2026-04-02T13:13:51.299Z

cve-icon NVD

Status : Received

Published: 2026-04-02T13:16:27.210

Modified: 2026-04-02T14:16:33.723

Link: CVE-2026-4636

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.