RHSA-2026:6476 - Security Advisory

Topic

New images are available for Red Hat build of Keycloak 26.2.15 and Red Hat build of Keycloak 26.2.15 Operator, running on OpenShift Container Platform

Description

Red Hat build of Keycloak is an integrated sign-on solution, available as a Red Hat JBoss Middleware for OpenShift containerized image. The Red Hat build of Keycloak for OpenShift image provides an authentication server that you can use to log in centrally, log out, and register. You can also manage user accounts for web applications, mobile applications, and RESTful web services.
Red Hat build of Keycloak Operator for OpenShift simplifies deployment and management of Keycloak 26.2.15 clusters.

This erratum releases new images for Red Hat build of Keycloak 26.2.15 for use within the OpenShift Container Platform cloud computing Platform-as-a-Service (PaaS) for on-premise or private cloud deployments, aligning with the standalone product release.

Security fixes:

• Information disclosure due to redirect_uri validation bypass (CVE-2026-3872)
• Replay of action tokens via improper handling of single-use entries (CVE-2026-4325)
• UMA policy bypass allows authenticated users to gain unauthorized access to victim-owned resources ( CVE-2026-4636)
• Privilege escalation via forged authorization codes due to SingleUseObjectProvider isolation flaw (CVE-2026-4282)
• Denial of Service via excessive processing of OpenID Connect scope parameters (CVE-2026-4634)

Solution

Before applying the update, back up your existing installation, including all applications, configuration files, databases and database settings, and so on.

Affected Products

• Red Hat build of Keycloak Text-only Advisories x86_64

Fixes

CVEs

• CVE-2026-3872
• CVE-2026-4282
• CVE-2026-4325
• CVE-2026-4634
• CVE-2026-4636

References

• https://access.redhat.com/security/updates/classification/#important