I was in a game today, and there was some one said they were going to "break my internet".

I assumed it was all bluff so I ignored it and carried on. Then after i left the game my internet stopped working!!

The problem was with my router, i could connect to it, but it wouldnt connect to the internet.

Eventually i used an ethernet cord to bypass the router and got on bnet to talk to people about how to fix it. Then suddenly i started getting kicked off of bnet and when id try to log in would get the "cd key is already logged in" message, but could log back in after waiting a few minutes.

Eventually i reset my router, and everything started working again.

My question is, How can i make sure this doesn't happen to me again? What exactly did he do to mess with my router? Is my cd key compromised?

Thanks.

I'm not sure about what the person could have done, but the CDKey in use error is very likely to be caused by an improper disconnection from Battle.net. If your internet goes down or something you'll 'silently' disconnect from battle.net, so the server will still think you are connected. After a while the session will time out and you will be able to connect again... This is probably what happened. Usually when your CDKey is in use it will give you a name of who is using it, and this name is the one used when installing StarCraft. If this wasn't the name you entered then it could be possible someone has it.

With proper tools it's entirely possible to identify your IP address via bnet.
With that one can launch any number of attacks against your system.

Denial of Service (DoS) attacks, for example, aren't too hard to initiate with proper tools. This attack floods your router with connection requests without ever finishing the connection process until the router can't create more connections. Since the connections were never fully established the connections never time out.
This doesn't terminate your existing connection to the battle.net but prevents new ones. After quitting the game your last free connection can be blocked too which effectively prevents you from communicating with anything outside your LAN.
Resetting the router resets the stuck connections and everything is back to normal, given the attack has stopped.
Note that all this works without any CDkeys or passwords being compromised.

I can't say if it actually was a DoS attack, but the symptoms match.

You can mitigate the problem by using proxies to connect to bnet or another easy way to change IP (my router has a button for that in its interface, but for most US providers that won't work).

On a side note, if you're concerned about losing your CD key, make sure you sign into your Battle.net Account and register it there. It guarantees that no one else can register your CD key, and it allows you to install StarCraft on any computer with an internet connection, no CD needed.

The best part, however, is that the digital download uses a much longer CD key which is many magnitudes harder for people on Battle.net to steal.

Basically, if you use your normal CD key on Battle.net, people you meet can easily steal it and kick you off forever. They can make sure you'll never be able to use that CD key ever again. If no one has done that to you yet, it's only because they haven't felt like it yet.

If you use the really long digital CD key from your Battle.net Account, this will never happen to you. For all intents and purposes, your CD key will be safe.

Post has been edited 1 time(s), last time on Apr 17 2014, 11:39 pm by Azrael.

Why does all this nasty stuff go on SC?

I play WC3 and SC2, and these things never happen.

I'm sorry. Once a guy was preventing (noone could join) me from making games for a really long time. But SC isn't my life goal, so I just quit playing for several months: less computer games the better, so I'm even grateful for that guy =)

Actually from what I read here and there with correct knowledge it's possible to resist attackers. I just was never really bothered with that. For instance you may block your router receiving messages from a given IP or a set of IPs. And there was a method posted by Zhuinden (here) to prevent stuff that was happening to me.