CVE-2026-4636

[CVE catalog]

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.

Severity

High · CVSS 8.1CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

Published

Apr 2, 2026, 12:30:00 PM UTC

Source

[NVD] · [CVE record]

EPSS

0.43% · Oct 27, 2026

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