Recently, research was published identifying a Tor exit node, located in Russia, that was consistently and maliciously modifying any uncompressed Windows executables downloaded through it. Naturally this piqued our interest, so we decided to peer down the rabbit hole. Suffice to say, the hole was a lot deeper than we expected!
more here..........http://www.f-secure.com/weblog/archives/00002764.html
more here..........http://www.f-secure.com/weblog/archives/00002764.html