A flaw was found in the Pushed Authorization Request PAR implementation of the keycloak-services component. The issue occurs when an authentication flow is restarted, which incorrectly clears the internal markers used to track PAR consumption while leaving the request active. This allows an attacker to reuse the same authorization request to obtain multiple access tokens, bypassing security requirements for single-use requests.

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History

Thu, 29 Oct 2026 08:00:00 +0000

Type Values Removed Values Added
First Time appeared Red Hat
Red Hat red Hat Build Of Keycloak 26.4
Redhat build Of Keycloak
Redhat single Sign-on
Vendors & Products Red Hat
Red Hat red Hat Build Of Keycloak 26.4
Redhat build Of Keycloak
Redhat single Sign-on

Thu, 29 Oct 2026 06:30:00 +0000

Type Values Removed Values Added
Description A flaw was found in the Pushed Authorization Request PAR implementation of the keycloak-services component. The issue occurs when an authentication flow is restarted, which incorrectly clears the internal markers used to track PAR consumption while leaving the request active. This allows an attacker to reuse the same authorization request to obtain multiple access tokens, bypassing security requirements for single-use requests.
Title Keycloak-services: keycloak-services: par single-use bypass via flow restart
First Time appeared Redhat
Redhat build Keycloak
Redhat red Hat Single Sign On
Weaknesses CWE-670
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
Metrics cvssV3_1

{'score': 5.4, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N'}


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cve-icon MITRE

Status: PUBLISHED

Assigner: redhat

Published:

Updated: 2026-10-29T06:22:11.710Z

Reserved: 2026-10-27T14:02:45.318Z

Link: CVE-2026-117859

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-10-29T07:16:44.840

Modified: 2026-10-29T07:16:44.957

Link: CVE-2026-117859

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-10-29T07:45:14Z

Weaknesses