---
id: CVE-2026-1609
title: A flaw was found in Keycloak
summary: >-
  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…
severity: high
cvss: 8.1
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N'
cwe:
  - CWE-284
  - CWE-284
vendor: redhat
product: build_of_keycloak
affected:
  - build_of_keycloak = 26.5.2
published: '2026-07-16'
updated: '2026-08-09'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-1609'
references:
  - url: 'https://access.redhat.com/security/cve/CVE-2026-1609'
    label: secalert@redhat.com
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2435257'
    label: secalert@redhat.com
  - url: 'https://github.com/keycloak/keycloak/issues/46144'
    label: secalert@redhat.com
  - url: 'https://github.com/keycloak/keycloak/releases/tag/26.5.3'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/security/cve/CVE-2026-1609'
    label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2435257'
    label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-1609.json
    label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
tags:
  - nvd
epss: 0.00562
epssPercentile: 0.45548
ingestedAt: '2026-08-09T15:33:36.193Z'
---

## Overview

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.

## Affected

- `build_of_keycloak = 26.5.2`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.