Wow. This is the dumbest response I have ever heard of. This is the IGNORANCE we have to deal with today throughout the world. Please, do not post if you have no evidence. Because the fact is, that the 1,000+ players hosting on Blockland could have been hacked, and you wouldn't know it, they wouldn't know it, NO ONE WOULD KNOW IT but the perpetrator.
Please. Do not post crap.
Obviously you know nothing about ports. What he posted wasn't crap, but it was pretty true. If people had a virus from opening there ports, they would probably not be hosting at all.
We all have plenty of ports open already. I don't see any viruses magically coming into my computer and taking it over. I have never had a virus problem in my 6 years of having 3 different computers. First one burnt out the ram card from playing too much 3D games (Crappy Laptop), second one I spilled apple cider all over it, and it stopped working. The computer I have now, is perfectly fine. On all 3 of my computers, I have had my ports open for Blockland. Not to mention that on this computer I have it forwarded for Grand Theft Auto Vice City, Grand Theft Auto San Andreas, Team Fortress 2, Garry's Mod, Teeworlds, Dawn of War, Counterstrike, and I believe a few more. I've had this for over a year.
All port forwarding is, is allowing data transfer through a specific wire in a cable. You know that Ethernet Cable you use to plug into your router? That has tiny little wires in it. All port forwarding does is unblock one tiny wire so it allows data through. Like server information and whatnot. I really don't think there is any way to get a virus from this. The only way you can get a virus these days is being stupid browsing the internet, or someone planting it on your computer Via flash drive or something.
You see, we already have ports open for internet, remote desktop features, and other things. Viruses can already get through there, but only if you intentionally download it, or you fall for a fake virus scanning pop-up, then end up downloading that. Or, if you think spam emails are real, and that can get you a virus. The internet wouldn't work if we had every single port closed.
TL:DR: Some ports are already open on your computer. I have a million ports already open for my games. Virus only get's through if you allow it, by download, email, or pop-up trickery.
I'm sure there are other ways, but they are rare.
Now have fun,
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