{"id":"CVE-2026-4634","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-4634","summary":"A flaw was found in Keycloak. An unauthenticated attacker can exploit this vulnerability by sending a specially crafted POST request with an excessively long scope parameter to the…","details":"A flaw was found in Keycloak. An unauthenticated attacker can exploit this vulnerability by sending a specially crafted POST request with an excessively long scope parameter to the OpenID Connect (OIDC) token endpoint. This leads to high resource consumption and prolonged processing times, ultimately resulting in a Denial of Service (DoS) for the Keycloak server.","published":"2026-04-02T12:44:53.424Z","modified":"2026-07-15T00:50:36.563Z","cvss":{"score":7.5,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[],"fix":null,"references":[{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:6475"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:6476"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:6477"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:6478"},{"type":"WEB","url":"https://access.redhat.com/security/cve/CVE-2026-4634"},{"type":"REPORT","url":"https://bugzilla.redhat.com/show_bug.cgi?id=2450250"},{"type":"WEB","url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-4634.json"}],"provenance":{"sources":["OSV.dev","NVD","FIRST.org (EPSS)"],"lastVerified":"2026-07-15T00:50:36.563Z"}}