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.
Affected products
redhat: build of keycloak
References10
- access.redhat.com/errata/RHSA-2026:6475 Vendor Advisory
- access.redhat.com/errata/RHSA-2026:6476 Vendor Advisory
- access.redhat.com/errata/RHSA-2026:6477 Vendor Advisory
- access.redhat.com/errata/RHSA-2026:6478 Vendor Advisory
- access.redhat.com/security/cve/CVE-2026-4636 Vendor Advisory
- bugzilla.redhat.com/show_bug.cgi?id=2450251 ExploitIssue TrackingVendor Advisory
- access.redhat.com/errata/RHSA-2026:6475 Vendor Advisory
- access.redhat.com/errata/RHSA-2026:6476 Vendor Advisory
- access.redhat.com/errata/RHSA-2026:6477 Vendor Advisory
- access.redhat.com/errata/RHSA-2026:6478 Vendor Advisory
Metrics
- CVSS 3.1
-
8.1
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N - EPSS — exploit probability
- 0% percentile: 38 · as of 12 November 2026
- CWE
- CWE-551
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