CVE-2026-4636 in Keycloak
Summary
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.
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Responsible
redhat
Reservation
03/23/2026
Disclosure
04/02/2026
Entries
VulDB provides additional information and datapoints for this CVE:
| ID | Vulnerability | CWE | Exp | Cou | CVE |
|---|---|---|---|---|---|
| 354867 | Keycloak incorrect behavior order | 551 | Not defined | Not defined | CVE-2026-4636 |