CVE-2026-4636 (GCVE-0-2026-4636)
Vulnerability from cvelistv5
Published
2026-04-02 12:45
Modified
2026-04-02 16:35
CWE
  • CWE-551 - Incorrect Behavior Order: Authorization Before Parsing and Canonicalization
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.
References
https://access.redhat.com/errata/RHSA-2026:6475 vendor-advisory, x_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:6476 vendor-advisory, x_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:6477 vendor-advisory, x_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:6478 vendor-advisory, x_refsource_REDHAT
https://access.redhat.com/security/cve/CVE-2026-4636 vdb-entry, x_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2450251 issue-tracking, x_refsource_REDHAT
Impacted products
Vendor Product Version
Red Hat Red Hat build of Keycloak 26.2 Unaffected: 26.2.15-1   < *
    cpe:/a:redhat:build_keycloak:26.2::el9
Create a notification for this product.
   Red Hat Red Hat build of Keycloak 26.2 Unaffected: 26.2-18   < *
    cpe:/a:redhat:build_keycloak:26.2::el9
Create a notification for this product.
   Red Hat Red Hat build of Keycloak 26.2 Unaffected: 26.2-18   < *
    cpe:/a:redhat:build_keycloak:26.2::el9
Create a notification for this product.
   Red Hat Red Hat build of Keycloak 26.2.15     cpe:/a:redhat:build_keycloak:26.2::el9
Create a notification for this product.
   Red Hat Red Hat build of Keycloak 26.4 Unaffected: 26.4.11-1   < *
    cpe:/a:redhat:build_keycloak:26.4::el9
Create a notification for this product.
   Red Hat Red Hat build of Keycloak 26.4 Unaffected: 26.4-14   < *
    cpe:/a:redhat:build_keycloak:26.4::el9
Create a notification for this product.
   Red Hat Red Hat build of Keycloak 26.4 Unaffected: 26.4-14   < *
    cpe:/a:redhat:build_keycloak:26.4::el9
Create a notification for this product.
   Red Hat Red Hat build of Keycloak 26.4.11     cpe:/a:redhat:build_keycloak:26.4::el9
Create a notification for this product.
Show details on NVD website


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