I've noticed that when I'm connected to the internet through a VPN service, all of the ports on my system are either closed or ''stealthed' except for port 443 (which is open) -- and sometimes 220. When I connect directly with my ISP (no VPN) all seems to be okay. I'm not sure I understand this -- and I definitely don't understand what it means, but is it a problem or is it nothing to worry about?
With the VPN connected, you're scanning the VPN server, and not your local machine. If port 443 is open on the server, maybe it's listening for VPN connections. Is your VPN client perchance using port 443? If so, that means that the VPN server is both an entry and an exit, which is iffy security practice. I'm not sure about port 220. Maybe SSH? You could try connecting via SSH in terminal, and see if you get a response. Also, port scans often test only the lowest 1056 ports. You might also check port 1194, which is the default for OpenVPN in UDP mode. Anyway, for the most part, this isn't something to worry about.
