Description
A flaw was found in Keycloak. A significant Broken Access Control vulnerability exists in the UserManagedPermissionService (UMA Protection API). When updating or deleting a UMA policy associated with multiple resources, the authorization check only verifies the caller's ownership against the first resource in the policy's list. This allows a user (Owner A) who owns one resource (RA) to update a shared policy and modify authorization rules for other resources (e.g., RB) in that same policy, even if those other resources are owned by a different user (Owner B). This constitutes a horizontal privilege escalation.
Metrics
CVSS 3.1 5.4/10
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:NWeakness enumeration
Affected software
| Vendor | Product | Versions |
|---|---|---|
| Red Hat | Red Hat build of Keycloak 26.2 | — |
| Red Hat | Red Hat build of Keycloak 26.2 | — |
| Red Hat | Red Hat build of Keycloak 26.2 | — |
| Red Hat | Red Hat build of Keycloak 26.2.13 | — |
| Red Hat | Red Hat build of Keycloak 26.4 | — |
| Red Hat | Red Hat build of Keycloak 26.4 | — |
| Red Hat | Red Hat build of Keycloak 26.4 | — |
| Red Hat | Red Hat build of Keycloak 26.4.9 | — |
References
Timeline
- Published
- Feb 9, 2026
- Last modified
- Jun 17, 2026
- NVD status
- Deferred