Althought not widespread, a few players have reported that a security exploit, called the man-in-the-middle attack, allows attackers to act as the “middle man” between you and logging into World of Warcraft. Basically, when you try to log into World of Warcraft, you are actually not. Instead, you are providing the attacker your information, including your authenticator code. This leads the attacker to log into your account.
Now this is a very isolated attack, so do NOT panic and remove your authenticator! Again, very isolated and will not affect you if you have a good virus scanner installed. If you don’t have an antivirus program installed, there are great free ones out there.