A log injection flaw was found in Keycloak, related to the WebAuthn authentication mode. This issue allows a text string to be injected through the authentication form, which may have a minor impact on the logs' integrity. The flaw is caused by errors in the browser client during setup or authentication with "Security Key login" (WebAuthn) being written into the form, sent to Keycloak, and logged without escaping, thus allowing log injection.