There are several ways this could happen.
The most obvious is a keylogger. Not all of those are discovered, there are some nasty pieces out there. But the really hard to detect ones are used for stealing bank and creditcard stuff, not online game stuff.
I would put my money on this one.
Next would be a 'brute force' on the e-mail account. It is (or was till recently, didn't try) possible to figure out if an account is valid or not for GW. I've seen at least two verify's of that on my secondary account. And a brute force can happen over days, if you have like 10.000 or more valid e-mail accounts and you scan all of them slowly you won't generate many time-outs on the accounts. Once you have access you determine if there is something valuable. If so, rob. If not, just wait till there is something valuable. You have the credentials and as long as those don't change you have access.
Next step is an compromised e-mail account. This one would apply if the account uses the same credentials as the actual login for GW.
The hacker gets into the e-mail account and can log in with the same password on GW.
The same thing could be true for a compromised database from a forum/fansite that didn't encrypt and salt the passwords. Storing MD5 hashes of passwords looks smart, but is vulnerable to dictionary attack. In this case the dictionary is just translating MD5 hashes to their regular counterparts. Or brute-force them, but that could take a long time.
The least obvious hack would be a server hack. It could happen, but it's far easier to target a massive number of end-users with on average low security practices than targetting a limited number of servers which are on a hardened infrastructure.
And even if they got on a server, my guess is that the servers containing the login credentials are even more secured and only used for verifying credentials. And those don't have the passwords in plain text in the database.
Only thing I could check out with a packet-sniffer would be if the client sends out plain text UID/password to the server or that this is hashed/encrypted on client side.
Last but not least there is also the possibility that the entire story is not true.
We have to assume that the OP and others are speaking the truth in this matter but there is no way to verify that.
But it remains guessing what happened but like I said before, I would put my money on a keylogger.
Edit:
Quote:
I asked a friend of mine who is studying SECURITY to try to hack me (he knows the tricks) HE WAS UNABLE TO DO IT & told me that I cannot be hacked.
|
Well, he is still studying

Trying to enter a system from the outside might be hard, but getting you to install this very nice and shiny and very fun game is probably a lot easier. And it's a very nice game indeed, you can even play it online with your friends.
And it was one of your friends that send it.
So you open up your firewall to play with your friends and at the same time you allow other data to flow out as well.
Everyone is vulnerable to social engineering.