A vulnerability in Keycloak's SAML protocol implementation allows an attacker to exploit the HTTP-Redirect binding when a client is configured with a wildcard redirect URL. This flaw can cause service providers to process attacker-supplied parameters instead of legitimate login data, potentially resulting in users being logged into incorrect accounts. The issue has a low CVSS score of 3.4 and does not have known exploits in the wild. Red Hat has released fixed images for Keycloak 26.4.17 addressing this and other vulnerabilities.