Quote Originally Posted by Silence View Post
I'm pretty sure this isn't how the current man-in-middle attack works.

Your first attempt will be captured and used to log in. You will just be thinking you made a typo and enter a new code again and you can log in. They do not let you use the first code entered as the expiration has been present for a long time... we have posts about that on the forum here going way back when they made this change. You can still log in on multiple accounts with the same authenticator code at the same time.

In the mean time they will be messing around on the website doing whatever. Granted they can't do too much besides changing your password. But the next time you try to log in they will use your authenticator code to actually log in to the game and rip it.
The old attacks were replay attacks, and they were capturing the battlnet authentication via a trojan. They were not actively blocking the data going from you to blizzard, they were just listening to it, and then replaying it. That's when blizzard changed it to a single log in from one key.