CVE-2026-4636
High
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.
SeverityHigh
CVSS8.1
Exploit probability—
Product
Redhat Build Of Keycloak
PublishedApr 2, 2026
First seenApr 2, 2026
Weakness typeCWE-551CWE-551
How to fix
Update
- org.keycloak:keycloak-services26.5.7 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| redhat build_of_keycloak | No range specified, 26.2, 26.2.15, 26.4, 26.4.11 | — |
| org.keycloak:keycloak-servicesMaven | v < 26.5.7 | 26.5.7 |
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