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VULNERABILITIES

CVE-2026-4636 Details

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.

Metrics

CVSS 3.x Severity and Vector Strings:

CNA: redhat-SADPCVSS-B:8.1 HIGHVector:CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

References to Advisories, Solutions, and Tools

By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.

URLSource(s)Tag(s)
https://access.redhat.com/errata/RHSA-2026:6475 redhat-SADPVendor Advisory
https://access.redhat.com/errata/RHSA-2026:6476 redhat-SADPVendor Advisory
https://access.redhat.com/errata/RHSA-2026:6477 redhat-SADPVendor Advisory
https://access.redhat.com/errata/RHSA-2026:6478 redhat-SADPVendor Advisory
https://access.redhat.com/security/cve/CVE-2026-4636 redhat-SADPVendor Advisory

see all 13 references

Weakness Enumeration

CWE-IDCWE NameSource
CWE-551Incorrect Behavior Order: Authorization Before Parsing and Canonicalizationredhat-SADP
CWE-551Incorrect Behavior Order: Authorization Before Parsing and Canonicalization[email protected]

Affected Products

ProductVersions
redhat build of keycloak
26.2
26.2.15
26.4
26.4.11

CPE

  • cpe:2.3:a:redhat:build_of_keycloak:-:*:*:*:text-only:*:*:*
  • cpe:2.3:a:redhat:build_of_keycloak:26.2:*:*:*:text-only:*:*:*
  • cpe:2.3:a:redhat:build_of_keycloak:26.2.15:*:*:*:text-only:*:*:*
  • cpe:2.3:a:redhat:build_of_keycloak:26.4:*:*:*:text-only:*:*:*
  • cpe:2.3:a:redhat:build_of_keycloak:26.4.11:*:*:*:text-only:*:*:*

Remediation

  • No remediation found in references.

Change History

8 change records found show changes

QUICK INFO

CVE Dictionary Entry:
CVE-2026-4636
NVD Published Date:
Apr 2, 2026
NVD Last Modified:
Jul 15, 2026
Source:
[email protected]
CVE-2026-4636 Details - Not Deferred