A flaw was found in the TokenManager component of Keycloak, an open-source identity and access management solution. The issue occurs during the validation of stateless access tokens when the original user ID no longer exists. Keycloak incorrectly falls back to using the username to identify the user without verifying if the identity matches the original token subject. This could allow an attacker with an old token to gain access to a newly created service account if it shares the same client ID as a previously deleted one.
Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.


Workaround

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.

History

Fri, 06 Nov 2026 06:15:00 +0000

Type Values Removed Values Added
Title keycloak-services: keycloak-services: Stateless token preferred_username fallback enables identity rebinding Keycloak-services: keycloak-services: stateless token preferred_username fallback enables identity rebinding
First Time appeared Redhat
Redhat build Keycloak
Redhat red Hat Single Sign On
CPEs cpe:/a:redhat:build_keycloak:
cpe:/a:redhat:red_hat_single_sign_on:7
Vendors & Products Redhat
Redhat build Keycloak
Redhat red Hat Single Sign On
References

Fri, 06 Nov 2026 00:15:00 +0000

Type Values Removed Values Added
Description A flaw was found in the TokenManager component of Keycloak, an open-source identity and access management solution. The issue occurs during the validation of stateless access tokens when the original user ID no longer exists. Keycloak incorrectly falls back to using the username to identify the user without verifying if the identity matches the original token subject. This could allow an attacker with an old token to gain access to a newly created service account if it shares the same client ID as a previously deleted one.
Title keycloak-services: keycloak-services: Stateless token preferred_username fallback enables identity rebinding
Weaknesses CWE-287
References
Metrics threat_severity

None

cvssV3_1

{'score': 4.2, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N'}

threat_severity

Moderate


Projects

Sign in to view the affected projects.

cve-icon MITRE

Status: PUBLISHED

Assigner: redhat

Published:

Updated: 2026-11-06T06:02:51.358Z

Reserved: 2026-09-23T09:37:33.249Z

Link: CVE-2026-96447

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-11-06T06:16:44.910

Modified: 2026-11-06T06:16:45.027

Link: CVE-2026-96447

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-11-05T00:00:00Z

Links: CVE-2026-96447 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-11-06T02:30:14Z

Weaknesses