CVE-2026-1609
Org.keycloak/keycloak-quarkus-server: keycloak: unauthorized access via jwt authorization grant with disabled users
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.
INFO
Published Date :
July 16, 2026, 1:16 a.m.
Last Modified :
July 16, 2026, 1:16 a.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-1609
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | 53f830b8-0a3f-465b-8143-3b8a9948e749 | ||||
| CVSS 3.1 | HIGH | [email protected] |
Solution
- Ensure user status is validated during JWT authorization.
- Patch Keycloak to fix JWT validation flaw.
- Review and secure JWT authorization grant processing.
- Disable JWT authorization grant preview if not needed.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-1609.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-1609 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-1609
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-1609 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-1609 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Jul. 16, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'Keycloak', 'product': 'Keycloak', 'versions': [{'status': 'affected', 'version': '26.5.0', 'lessThan': '26.5.3', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}, {'cpes': ['cpe:/a:redhat:jboss_enterprise_application_platform:8'], 'vendor': 'Red Hat', 'product': 'Red Hat JBoss Enterprise Application Platform 8', 'packageName': 'keycloak-quarkus-server', 'collectionURL': 'https://access.redhat.com/jbossnetwork/restricted/listSoftware.html', 'defaultStatus': 'unaffected'}, {'cpes': ['cpe:/a:redhat:jboss_enterprise_application_platform:8'], 'vendor': 'Red Hat', 'product': 'Red Hat JBoss Enterprise Application Platform 8', 'packageName': 'keycloak-quarkus-server-app', 'collectionURL': 'https://access.redhat.com/jbossnetwork/restricted/listSoftware.html', 'defaultStatus': 'unaffected'}, {'cpes': ['cpe:/a:redhat:jboss_enterprise_application_platform:8'], 'vendor': 'Red Hat', 'product': 'Red Hat JBoss Enterprise Application Platform 8', 'packageName': 'keycloak-quarkus-server-deployment', 'collectionURL': 'https://access.redhat.com/jbossnetwork/restricted/listSoftware.html', 'defaultStatus': 'unaffected'}, {'cpes': ['cpe:/a:redhat:jbosseapxp'], 'vendor': 'Red Hat', 'product': 'Red Hat JBoss Enterprise Application Platform Expansion Pack', 'packageName': 'keycloak-quarkus-server', 'collectionURL': 'https://access.redhat.com/jbossnetwork/restricted/listSoftware.html', 'defaultStatus': 'unaffected'}, {'cpes': ['cpe:/a:redhat:jbosseapxp'], 'vendor': 'Red Hat', 'product': 'Red Hat JBoss Enterprise Application Platform Expansion Pack', 'packageName': 'keycloak-quarkus-server-app', 'collectionURL': 'https://access.redhat.com/jbossnetwork/restricted/listSoftware.html', 'defaultStatus': 'unaffected'}, {'cpes': ['cpe:/a:redhat:jbosseapxp'], 'vendor': 'Red Hat', 'product': 'Red Hat JBoss Enterprise Application Platform Expansion Pack', 'packageName': 'keycloak-quarkus-server-deployment', 'collectionURL': 'https://access.redhat.com/jbossnetwork/restricted/listSoftware.html', 'defaultStatus': 'unaffected'}] Added 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. Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N Added CWE CWE-284 Added Reference https://access.redhat.com/security/cve/CVE-2026-1609 Added Reference https://bugzilla.redhat.com/show_bug.cgi?id=2435257 Added Reference https://github.com/keycloak/keycloak/issues/46144 Added Reference https://github.com/keycloak/keycloak/releases/tag/26.5.3