LDAP Endpoint Vulnerability Allows Credentials Leakage

Summary

A vulnerability was found in Keycloak. The LDAP testing endpoint allows changing the Connection URL  independently without re-entering the currently configured LDAP bind credentials. This flaw allows an attacker with admin access (permission manage-realm) to change the LDAP host URL ("Connection URL") to a machine they control. The Keycloak server will connect to the attacker's host and try to authenticate with the configured credentials, thus leaking them to the attacker. As a consequence, an attacker who has compromised the admin console or compromised a user with sufficient privileges can leak domain credentials and attack the domain.