A flaw was found in Keycloak. When deployed in stateless mode with MySQL or MariaDB, a mismatch in row-count semantics between the database driver and Keycloak's application logic allows an attacker to bypass replay protection. This vulnerability enables an attacker who intercepts single-use security artifacts, such as JWT client assertions, DPoP proofs, or one-time password (TOTP) codes, to replay them. Successful exploitation grants unauthorized access to the token endpoint or login flow.
History

Tue, 22 Sep 2026 19:30:00 +0000


Tue, 22 Sep 2026 19:00:00 +0000

Type Values Removed Values Added
Title Keycloak: Replay protection bypass leads to unauthorized access via database driver semantics mismatch Keycloak-services: keycloak: replay protection bypass leads to unauthorized access via database driver semantics mismatch
First Time appeared Redhat
Redhat build Keycloak
CPEs cpe:/a:redhat:build_keycloak:
Vendors & Products Redhat
Redhat build Keycloak
References

Mon, 21 Sep 2026 22:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Fri, 18 Sep 2026 07:45:00 +0000

Type Values Removed Values Added
First Time appeared Keycloak
Keycloak keycloak
Vendors & Products Keycloak
Keycloak keycloak

Thu, 17 Sep 2026 19:00:00 +0000

Type Values Removed Values Added
Title keycloak-services: Keycloak: Replay protection bypass leads to unauthorized access via database driver semantics mismatch Keycloak: Replay protection bypass leads to unauthorized access via database driver semantics mismatch
References

Thu, 17 Sep 2026 12:15:00 +0000

Type Values Removed Values Added
Description A flaw was found in Keycloak. When deployed in stateless mode with MySQL or MariaDB, a mismatch in row-count semantics between the database driver and Keycloak's application logic allows an attacker to bypass replay protection. This vulnerability enables an attacker who intercepts single-use security artifacts, such as JWT client assertions, DPoP proofs, or one-time password (TOTP) codes, to replay them. Successful exploitation grants unauthorized access to the token endpoint or login flow.
Title keycloak-services: Keycloak: Replay protection bypass leads to unauthorized access via database driver semantics mismatch
Weaknesses CWE-294
References
Metrics threat_severity

None

cvssV3_1

{'score': 7.4, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N'}

threat_severity

Important


cve-icon MITRE

Status: PUBLISHED

Assigner: redhat

Published: 2026-09-17T18:47:34.059Z

Updated: 2026-09-25T06:42:50.534Z

Reserved: 2026-09-14T14:53:37.815Z

Link: CVE-2026-90997

cve-icon Vulnrichment

Updated: 2026-09-21T21:07:48.577Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-09-17T19:17:06.740

Modified: 2026-09-22T19:16:56.183

Link: CVE-2026-90997

cve-icon Redhat

Severity : Important

Publid Date: 2026-09-16T14:21:23Z

Links: CVE-2026-90997 - Bugzilla