{"id":"CVE-2026-0976","revision":"cff20f737a364abfbfe493ebf0580072","records":[{"revision":"cff20f737a364abfbfe493ebf0580072","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-0976","aliases":[],"title":"Org.keycloak/keycloak-quarkus-server: keycloak: proxy bypass due to improper handling of matrix parameters in url paths","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.","state":0,"publishedAt":"2026-01-15T12:06:21.251+00:00","modifiedAt":"2026-10-22T21:17:19.726+00:00","affected":[{"ecosystem":"https://access.redhat.com/downloads/content/package-browser/","name":"Red Hat build of Keycloak 26.4.9","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Red Hat\",\n                    \"product\": \"Red Hat build of Keycloak 26.4.9\",\n                    \"collectionURL\": \"https://access.redhat.com/downloads/content/package-browser/\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"cpes\": [\n                        \"cpe:/a:redhat:build_keycloak:26.4::el9\"\n                    ]\n                }"},{"ecosystem":"https://access.redhat.com/downloads/content/package-browser/","name":"keycloak-quarkus-server","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Red Hat\",\n                    \"product\": \"Red Hat Build of Keycloak\",\n                    \"collectionURL\": \"https://access.redhat.com/downloads/content/package-browser/\",\n                    \"packageName\": \"keycloak-quarkus-server\",\n                    \"defaultStatus\": \"affected\",\n                    \"cpes\": [\n                        \"cpe:/a:redhat:build_keycloak:\"\n                    ]\n                }"},{"ecosystem":"https://access.redhat.com/jbossnetwork/restricted/listSoftware.html","name":"keycloak-quarkus-server","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Red Hat\",\n                    \"product\": \"Red Hat JBoss Enterprise Application Platform 8\",\n                    \"collectionURL\": \"https://access.redhat.com/jbossnetwork/restricted/listSoftware.html\",\n                    \"packageName\": \"keycloak-quarkus-server\",\n                    \"defaultStatus\": \"affected\",\n                    \"cpes\": [\n                        \"cpe:/a:redhat:jboss_enterprise_application_platform:8\"\n                    ]\n                }"},{"ecosystem":"https://access.redhat.com/jbossnetwork/restricted/listSoftware.html","name":"keycloak-quarkus-server-app","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Red Hat\",\n                    \"product\": \"Red Hat JBoss Enterprise Application Platform 8\",\n                    \"collectionURL\": \"https://access.redhat.com/jbossnetwork/restricted/listSoftware.html\",\n                    \"packageName\": \"keycloak-quarkus-server-app\",\n                    \"defaultStatus\": \"affected\",\n                    \"cpes\": [\n                        \"cpe:/a:redhat:jboss_enterprise_application_platform:8\"\n                    ]\n                }"},{"ecosystem":"https://access.redhat.com/jbossnetwork/restricted/listSoftware.html","name":"keycloak-quarkus-server-deployment","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Red Hat\",\n                    \"product\": \"Red Hat JBoss Enterprise Application Platform 8\",\n                    \"collectionURL\": \"https://access.redhat.com/jbossnetwork/restricted/listSoftware.html\",\n                    \"packageName\": \"keycloak-quarkus-server-deployment\",\n                    \"defaultStatus\": \"affected\",\n                    \"cpes\": [\n                        \"cpe:/a:redhat:jboss_enterprise_application_platform:8\"\n                    ]\n                }"},{"ecosystem":"https://access.redhat.com/jbossnetwork/restricted/listSoftware.html","name":"keycloak-quarkus-server","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Red Hat\",\n                    \"product\": \"Red Hat JBoss Enterprise Application Platform Expansion Pack\",\n                    \"collectionURL\": \"https://access.redhat.com/jbossnetwork/restricted/listSoftware.html\",\n                    \"packageName\": \"keycloak-quarkus-server\",\n                    \"defaultStatus\": \"affected\",\n                    \"cpes\": [\n                        \"cpe:/a:redhat:jbosseapxp\"\n                    ]\n                }"},{"ecosystem":"https://access.redhat.com/jbossnetwork/restricted/listSoftware.html","name":"keycloak-quarkus-server-app","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Red Hat\",\n                    \"product\": \"Red Hat JBoss Enterprise Application Platform Expansion Pack\",\n                    \"collectionURL\": \"https://access.redhat.com/jbossnetwork/restricted/listSoftware.html\",\n                    \"packageName\": \"keycloak-quarkus-server-app\",\n                    \"defaultStatus\": \"affected\",\n                    \"cpes\": [\n                        \"cpe:/a:redhat:jbosseapxp\"\n                    ]\n                }"},{"ecosystem":"https://access.redhat.com/jbossnetwork/restricted/listSoftware.html","name":"keycloak-quarkus-server-deployment","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Red Hat\",\n                    \"product\": \"Red Hat JBoss Enterprise Application Platform Expansion Pack\",\n                    \"collectionURL\": \"https://access.redhat.com/jbossnetwork/restricted/listSoftware.html\",\n                    \"packageName\": \"keycloak-quarkus-server-deployment\",\n                    \"defaultStatus\": \"affected\",\n                    \"cpes\": [\n                        \"cpe:/a:redhat:jbosseapxp\"\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N","score":3.7,"severity":"LOW"}],"references":["https://access.redhat.com/errata/RHSA-2026:2365","https://access.redhat.com/security/cve/CVE-2026-0976","https://bugzilla.redhat.com/show_bug.cgi?id=2429869"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-0976","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-0976","identifiers":["CVE-2026-0976"]},"retained":false,"historicalAffected":[]}],"coverage":[]}