Some services run really good behind a reverse proxy on 443, but some others can really become an hassle… And sometimes just opening other ports would be easier than to try configuring everything to work through 443.
An example that comes to my mind is SSH, yeah you can use SSLH to forward requests coming from 443 to 22, but it’s so much easier to just leave 22 open…
Now, for SSH, if you have certificate authentication or a strong password, I think you can feel quite safe, but what about other random ports? What risks I’m exposing my server to if I open some of them when needed for a service? Is the effort of trying to pass everything through 443/80 worth it?
There’s definitely nothing magic about ports 443 and 80. The risk is always that the underlying service will provide a vulnerability through which attackers could find a way. Any port presents an opportunity for attack; the security of the service is the is what makes it safe or not.
I’d argue that long tested services like
ssh, absent misconfiguration, are at least as safe as most reverse proxies. That doesn’t mean to say that people won’t try to break in via port 22. They sure will—they try on web ports too.