CVE-2026-1609 Org.keycloak/keycloak-quarkus-server: keycloak: unauthorized access via jwt authorization grant with disabled users
Attackers can bypass authentication for disabled users via JWT grants when the preview feature is enabled, gaining unauthorized access to sensitive resources.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-1609?
CVE-2026-1609 is a high-severity authentication bypass vulnerability in Redhat Build of Keycloak, published on 16 Jul 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
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.
Weakness: CWE-284
Which versions are affected by CVE-2026-1609?
1 open source package ship an affected version, including keycloak. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
keycloak Bitnami | From 26.5.2 | 26.5.3 |
Products include Redhat Build of Keycloak.
How do I fix CVE-2026-1609?
Upgrade keycloak to 26.5.3 or later.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-1609 being exploited?
There is no known exploitation of CVE-2026-1609 in the wild and no public exploit code.
Other vulnerabilities in Redhat Build of Keycloak
- CVE-2026-15572 Keycloak-services: keycloak-services: dcr protocol mapper type-swap policy bypass allows privilege escalation
- CVE-2026-3047 Keycloak SAML Broken has Authentication Bypass by Primary Weakness
- CVE-2026-15573 Keycloak-services: keycloak-services: authorization bypass via unnormalized uri matching in pathmatcher
- CVE-2026-16102 Keycloak-services: keycloak-services: default dcr policy allows role forgery via user property mappers
- CVE-2026-11800 Org.keycloak:keycloak-services: keycloak: authentication bypass via jwt algorithm confusion
Sources
Also known as BIT-keycloak-2026-1609, GHSA-5xcf-8m2w-ph6f.