CVE-2026-0976: low-severity vulnerability in Red Hat Build of Keycloak
Org.keycloak/keycloak-quarkus-server: keycloak: proxy bypass due to improper handling of matrix parameters in url paths
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8Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 3.7epss 0.5%
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.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
Affected products
Red Hat · Red Hat Build of KeycloakRed Hat · Red Hat build of Keycloak 26.4.9Red Hat · Red Hat JBoss Enterprise Application Platform 8Red Hat · Red Hat JBoss Enterprise Application Platform Expansion PackRelated CVEs — Red Hat Build of Keycloak
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