{"id":"BIT-keycloak-2026-9086","summary":"Keycloak: keycloak: cross-site scripting (xss) via case-insensitive uri validation bypass","details":"A flaw was found in Keycloak. A remote attacker with administrative privileges, specifically those with `manage-client` permission or access to client registration endpoints, could bypass client Uniform Resource Identifier (URI) validation. This is achieved by registering a malicious client with a specially crafted redirect URI using a case-insensitive `javascript:` or `data:` scheme. This Cross-Site Scripting (XSS) vulnerability allows for arbitrary code execution in the Keycloak origin when a victim clicks the crafted link, such as in the logout flow or the Admin Console.","aliases":["CVE-2026-9086"],"modified":"2026-09-08T08:48:06.915238367Z","published":"2026-08-25T11:42:40.305Z","database_specific":{"severity":"High","cpes":["cpe:2.3:a:redhat:build_of_keycloak:*:*:*:*:*:*:*:*","cpe:2.3:a:keycloak:keycloak:*:*:*:*:*:*:*:*"]},"references":[{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:30049"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:30050"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:30083"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:30084"},{"type":"ADVISORY","url":"https://access.redhat.com/security/cve/CVE-2026-9086"},{"type":"ADVISORY","url":"https://bugzilla.redhat.com/show_bug.cgi?id=2480170"},{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-9086"},{"type":"ADVISORY","url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-9086.json"}],"affected":[{"package":{"name":"keycloak","ecosystem":"Bitnami","purl":"pkg:bitnami/keycloak"},"ranges":[{"type":"SEMVER","events":[{"introduced":"26.4.0"},{"fixed":"26.4.13"},{"introduced":"26.6.0"},{"fixed":"26.6.4"}]}],"database_specific":{"source":"https://github.com/bitnami/vulndb/tree/main/data/keycloak/BIT-keycloak-2026-9086.json"},"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N"}]}],"schema_version":"1.9.0"}