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?
About 5 years ago I opened a port to run a test.
Within hours it was getting hammered (probably by scripts) trying to figure out what that port was forwarded to, and trying to connect.
I closed the port about a week later, but not before that poor consumer router was overwhelmed with the hits.
I closed the port after a week. For the next 2 years I’d get hammered with scans occasionally.
There are tools out there continually looking for open ports, they probably get added to a database and hackers/script kiddies, whoever, will try to get in.
Whats interesting is I did the same thing around 2000 with a DSL connection (which was very much a static address) and it wasn’t an issue even though there were fewer always-on consume connections.