Security researchers managed to take down a quarter of ZeroAccess, a botnet consisting of a peer-to-peer network of 1.9 million computers. The botnet is one of the largest Bitcoin mining botnets in the world, researchers estimate ZeroAccess raked in around US$2,165 worth of Bitcoins a day, resulting in an electricity consumption of US$561,000 a day on its victims' machines. On top of that, the botnet operators also earn plenty of money by generating fraudulent clicks on ads. Full details at TechWeekEurope.
Symantec operated a sinkhole to clear up ZeroAccess activity and during its research found each bot was using 257MB of network traffic every hour or 6.1GB a day, generating around 42 false ad clicks an hour. The botnet could therefore be generating tens of millions of dollars a year, to the detriment of ad networks.
There has been a cost for the environment too. Comparing the energy used by an idle PC, and an infected machine mining for Bitcoin, Symantec determined 1.82 KWh was being used per day by one victim machine. Multiplying that by 1.9 million gives 3,458 MWh per day – enough to power over 111,000 homes.
The botnet’s Bitcoin operation was only profitable because it used stolen electricity: it used about $561,000 (£347,000) of electricity a day on its victims’ machines, while only generating $2,165 (£1340) a day.