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Vulnerability record · CVE-2026-4636 · published 2 April 2026

CVE-2026-4636: Redhat build of keycloak vulnerability

Redhat · Build Of Keycloak

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.

8.1 CVSS 3.1 High EPSS 0.48% · top 60.8% CWE-551 · CWE-551
8.1CVSS 3.1 base score
0.48%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
13References, 2 tagged exploit
15 Jul 2026Last modified by NVD

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.

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

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://access.redhat.com/errata/RHSA-2026:6475 Vendor Advisory
https://access.redhat.com/errata/RHSA-2026:6476 Vendor Advisory
https://access.redhat.com/errata/RHSA-2026:6477 Vendor Advisory
https://access.redhat.com/errata/RHSA-2026:6478 Vendor Advisory
https://access.redhat.com/security/cve/CVE-2026-4636 Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2450251 ExploitIssue TrackingVendor Advisory
https://access.redhat.com/errata/RHSA-2026:6475 Vendor Advisory
https://access.redhat.com/errata/RHSA-2026:6476 Vendor Advisory
https://access.redhat.com/errata/RHSA-2026:6477 Vendor Advisory
https://access.redhat.com/errata/RHSA-2026:6478 Vendor Advisory
https://access.redhat.com/security/cve/CVE-2026-4636 Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2450251 ExploitIssue TrackingVendor Advisory
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-4636.json

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2026-4636), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.