CVE-2026-96446

Keycloak-services: keycloak-services: par single-use bypass via prompt=none silent authentication path

Published Sep 23, 2026 CVSS 3.1 · 4.2 Medium EPSS < 1% KEV · Not listed
Description
A flaw was found in the Pushed Authorization Request PAR implementation of Keycloak. The issue occurs when the silent authentication path prompt=none is used, which allows the authorization process to skip certain steps if a user is already logged in. Due to this bypass, the security rule that ensures a pushed request URI is used only once is not enforced. An attacker could potentially reuse a request URI to obtain multiple authorization codes for a user who is already signed in, violating security standards like FAPI-2.

Remediation

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.

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
CPEs cpe:/a:redhat:build_keycloak: cpe:/a:redhat:build_keycloak:26.6::el9
References
Type Values Removed Values Added
Metrics ssvc

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

Type Values Removed Values Added
First Time appeared Redhat build Of Keycloak
Redhat single Sign-on
Vendors & Products Redhat build Of Keycloak
Redhat single Sign-on
Type Values Removed Values Added
Description A flaw was found in the Pushed Authorization Request PAR implementation of Keycloak. The issue occurs when the silent authentication path prompt=none is used, which allows the authorization process to skip certain steps if a user is already logged in. Due to this bypass, the security rule that ensures a pushed request URI is used only once is not enforced. An attacker could potentially reuse a request URI to obtain multiple authorization codes for a user who is already signed in, violating security standards like FAPI-2.
Title Keycloak-services: keycloak-services: par single-use bypass via prompt=none silent authentication path
First Time appeared Redhat
Redhat build Keycloak
Redhat red Hat Single Sign On
Weaknesses CWE-862
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': 4.2, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
redhat
Published
Updated
Nov 6, 2026, 10:27 AM
Reserved
Sep 23, 2026, 9:32 AM
Status
Awaiting Analysis
Published
Sep 23, 2026, 12:17 PM
Modified
Nov 6, 2026, 11:17 AM
Severity
Moderate
Public date
Sep 22, 2026, 2:37 PM