Vulnerability in Keycloak
CVE-2026-1609
A flaw was found in Keycloak. When the JSON Web Token (JWT) authorization grant preview feature is enabled and a user account is disabled, Keycloak fails to validate the user’s disabled status during JWT authorization grant processing. A remote attacker with low privileges can exploit this improper access control vulnerability by presenting a valid assertion token from an external identity provider to obtain a JWT for a disabled user. This allows unauthorized access to sensitive resources.
EPSS: 0.006 (44.2th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N.
Affected products
- Keycloak — versions 26.5.0
- Red Hat Jboss Enterprise Application Platform 8
- Red Hat Jboss Enterprise Application Platform Expansion Pack
- Redhat Build_of_keycloak — versions 26.5.2
Weakness classification (CWE)
References
- secalert@redhat.com (x_refsource_REDHAT, vdb-entry, Vendor Advisory)
- secalert@redhat.com (x_refsource_REDHAT, issue-tracking, Issue Tracking, Vendor Advisory)
- secalert@redhat.com (Issue Tracking)
- secalert@redhat.com (Release Notes)
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c (Vendor Advisory)
Frequently asked questions
- What is CVE-2026-1609?
- CVE-2026-1609 is a high-severity vulnerability in Keycloak, classified under Improper Access Control. CVSS score: 8.1/10. Published 2026-07-16.
- How severe is CVE-2026-1609?
- High severity. CVSS v3 base score is 8.1 out of 10.