Gameover, also known as Gameover Zeus, is one of the most notorious botnets of recent times, used to grab covert control of innocent users computers and to borrow them to carry out cybercrime on a giant scale. The best-known criminal functionality of Gameover is probably its banking-related trickery, where it keeps track of what your computer is doing online until you start some sort of financial transaction. The U.S. Department of Justice (DoJ) suggests that the Gameover crooks have stolen more than $100,000,000 from users in the US alone.”]
Source: https://nakedsecurity.sophos.com/2014/06/03/has-cryptolocker-been-cracked-is-gameover-over/