OpenShift doesn't properly verify subdomain ownership, which allows route takeover. Once a custom route is created, the user must update the DNS provider by creating a canonical name (CNAME) record (if he likes to expose this route externally). The CNAME record should point the custom domain to the OpenShift router as the alias. In a case that the CNAME is not removed when the route is not in use anymore we are dealing with a dangling route. A malicious actor may take over the route.