I've only recently discovered the benefits of port forwarding (for hosting games and running torrent downloading programs) and though I only do it sparingly, I am curious as to the actual vulnerabilities of forwarding a port.
Everything I've read mentions "intrusions" of one form or another, but in very general terms. I hear the word trojan thrown around a lot, and I understand that there are trojans that exploit specific ports, but is that the only danger? I no longer use McAfee and instead opt for my router's firewall, and the applications I use that take advantage of port forwarding only for a very small range of ports.
Does allowing certain ports to be forwarded really open up my system to attack? Is the attack actually someone who is able to poke around my system, accessing and changing files and configurations, or is it merely something akin to a trojan; and if so, wouldn't my anti-virus (Norton Pro) detect it?
Thanks in advance for your time; I know I'll sleep a lot better knowing my downloads of TailSpin or Animaniacs episodes wasn't inviting the world to read my emails or change my router configurations.
Andrew