{"id":"CVE-2026-4874","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-4874","summary":"Keycloak Server-Side Request Forgery via OIDC token endpoint manipulation","details":"A flaw was found in Keycloak. An authenticated attacker can perform Server-Side Request Forgery (SSRF) by manipulating the `client_session_host` parameter during refresh token requests. This occurs when a Keycloak client is configured to use the `backchannel.logout.url` with the `application.session.host` placeholder. Successful exploitation allows the attacker to make HTTP requests from the Keycloak server’s network context, potentially probing internal networks or internal APIs, leading to information disclosure.","published":"2026-03-26T09:30:28Z","modified":"2026-09-10T03:50:36.368445797Z","cvss":{"score":3.1,"severity":"LOW","vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Maven","name":"org.keycloak:keycloak-services","fixedVersion":"26.6.3"},{"ecosystem":"Maven","name":"org.keycloak:keycloak-services","fixedVersion":"26.4.13"}],"fix":{"url":"https://github.com/keycloak/keycloak/pull/49682","label":"keycloak/keycloak#49682"},"references":[{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-4874"},{"type":"WEB","url":"https://github.com/keycloak/keycloak/issues/47935"},{"type":"WEB","url":"https://github.com/keycloak/keycloak/pull/49682"},{"type":"WEB","url":"https://github.com/keycloak/keycloak/pull/49685"},{"type":"WEB","url":"https://github.com/keycloak/keycloak/commit/00dd0dd716c4319d3bac3eb2f2ac22d2a94f79fd"},{"type":"WEB","url":"https://github.com/keycloak/keycloak/commit/63de0efd351a7a684212a042a12271908f63f0ee"},{"type":"WEB","url":"https://access.redhat.com/errata/RHSA-2026:25097"},{"type":"WEB","url":"https://access.redhat.com/errata/RHSA-2026:25098"},{"type":"WEB","url":"https://access.redhat.com/errata/RHSA-2026:30049"},{"type":"WEB","url":"https://access.redhat.com/errata/RHSA-2026:30050"},{"type":"WEB","url":"https://access.redhat.com/security/cve/CVE-2026-4874"},{"type":"WEB","url":"https://bugzilla.redhat.com/show_bug.cgi?id=2451611"},{"type":"PACKAGE","url":"https://github.com/keycloak/keycloak"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-09-10T03:50:36.368445797Z"}}