It’s simply inconceivable that Egerstad is the first person to do this sort of eavesdropping; Len Sassaman published a paper on this attack earlier this year. The price you pay for anonymity is exposing your traffic to shady people.

We don’t really know whether the Tor users were the accounts’ legitimate owners, or if they were hackers who had broken into the accounts by other means and were now using Tor to avoid being caught. But certainly most of these users didn’t realize that anonymity doesn’t mean privacy. The fact that most of the accounts listed by Egerstad were from small nations is no surprise; that’s where you’d expect weaker security practices.

More at Wired.com