A flaw was found in Keycloak. This improper input validation vulnerability occurs because Keycloak accepts RFC-compliant matrix parameters in URL path segments, while common reverse proxy configurations may ignore or mishandle them. A remote attacker can craft requests to mask path segments, potentially bypassing proxy-level path filtering. This could expose administrative or sensitive endpoints that operators believe are not externally reachable.
History

Thu, 15 Jan 2026 15:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

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


Thu, 15 Jan 2026 12:30:00 +0000

Type Values Removed Values Added
Description A flaw was found in Keycloak. This improper input validation vulnerability occurs because Keycloak accepts RFC-compliant matrix parameters in URL path segments, while common reverse proxy configurations may ignore or mishandle them. A remote attacker can craft requests to mask path segments, potentially bypassing proxy-level path filtering. This could expose administrative or sensitive endpoints that operators believe are not externally reachable.
Title Org.keycloak/keycloak-quarkus-server: keycloak: proxy bypass due to improper handling of matrix parameters in url paths
First Time appeared Redhat
Redhat build Keycloak
Redhat jboss Enterprise Application Platform
Redhat jbosseapxp
Weaknesses CWE-20
CPEs cpe:/a:redhat:build_keycloak:
cpe:/a:redhat:jboss_enterprise_application_platform:8
cpe:/a:redhat:jbosseapxp
Vendors & Products Redhat
Redhat build Keycloak
Redhat jboss Enterprise Application Platform
Redhat jbosseapxp
References
Metrics cvssV3_1

{'score': 3.7, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: redhat

Published:

Updated: 2026-01-15T14:45:41.540Z

Reserved: 2026-01-15T06:43:41.332Z

Link: CVE-2026-0976

cve-icon Vulnrichment

Updated: 2026-01-15T14:45:37.752Z

cve-icon NVD

Status : Received

Published: 2026-01-15T13:16:04.910

Modified: 2026-01-15T13:16:04.910

Link: CVE-2026-0976

cve-icon Redhat

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