CVE-2026-9086
No fix known EPSS <1%CVSS 7.3
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.
Products: Red Hat build of Keycloak 26.4, Red Hat build of Keycloak 26.4.13, Red Hat build of Keycloak 26.6, Red Hat build of Keycloak 26.6.4