I have used a default host with a self signed certificate and 444 for while. One advice was to make it support only the NULL cipher, but I did not succeed to do

I have used a default host with a self signed certificate and 444 for while. One advice was to make it support only the NULL cipher, but I did not succeed to do that, don't remember the details now. However, many scanners still end with a full 400. Either their implemenations are so bad or they intentionally send corrupted requests to try to exploit some vulnerability. I have not digged any deeper.