CVE-2026-0976GHSA-V897-PV23-R8CW
Org.keycloak/keycloak-quarkus-server: keycloak: proxy bypass due to improper handling of matrix parameters in url paths
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
CISA's decision points: whether it is exploited, whether attacks can be automated, and how much control an attacker gets. Assessed (SSVC 2.0.3).What do these mean? →
- Exploitation: none
- Automatable: no
- Technical impact: partial
Summary
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.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: partial
- Record last updated
Affected versions
- Red Hat Red Hat build of Keycloak 26.4.9
Version range not reported
- keycloak-quarkus-server
Version range not reported
- keycloak-quarkus-server
Version range not reported
- keycloak-quarkus-server-app
Version range not reported
- keycloak-quarkus-server-deployment
Version range not reported
- keycloak-quarkus-server
Version range not reported
- keycloak-quarkus-server-app
Version range not reported
- keycloak-quarkus-server-deployment
Version range not reported
- org.keycloak:keycloak-quarkus-serverMaven
through 26.2.5