Hundreds of global organisations have been infected by a Russian botnet as part of a cybercrime campaign that could be connected to the mysterious traffic spike that hit the Tor anonymity system in August, security firm Websense has suggested.
Using the Mevade botnet as its distribution mechanism, the campaign began on 23 July, successfully targeting a sizable number of organisations in sectors including (in order of infection rates) business services, manufacturing, government, transportation, healthcare and communications, the firm said.
The largest number of infections was recorded in the US, with smaller concentrations around Europe and South America. The absence of infections in Russia was unlikely to be a coincidence, indeed “the heavy use of attack infrastructure located in Ukraine and Russia and Mevade malware links this group to a potentially well-financed cyber-crime gang operating out of Kharkov, Ukraine and Russia,” said Websense’s research note.
The use of Mevade is telling. This botnet has already been forensically connected by several firms to the widely-reported and dramatic traffic spike that flooded the Tor system from 19 August onwards.
A number of theories have been put forward for this migration of Mevade to Tor, including that it was a clunky experimental attempt to hide the botnet's command and control. According to Websense the real reason was more likely an attempt to hide control of malware associated with campaign it has uncovered.
This brings Websense to the larger point of the Mevade campaign. The answer seems to be a bit of everything, including the staple for of crybercrime, click fraud and search hijacking. But the firm also noticed that the campaign included the '3proxy' reverse proxy tool that could be used to tunnel from the attackers straight through the NAT layer and into the target’s network. This is not something that commercial cybrcriminals would usually bother with.
“The use of reverse proxies indicates that the cyber-criminals plan to manually scan a network and move laterally towards more critical apps and information (such as databases, critical systems, source-code, and document repositories) than might exist on the original machine that has been compromised,” said Websense.
This sort of capability is certainly a lot more than a bit of faffing about with click fraud and suggests data theft as a capability. Used in concert with Mevade and Tor, Websense builds a convincing picture that this is more than a standard cybercrime campaign and includes a spot of freelance espionage.
Whatever this campaign is up to it’s more improvised than advanced and is certainly not in the league of Chinese APTs let alone US/Israeli Stuxnet, Duqu, Flame, Gauss cyber-weapons. If anything it looks more like a business move by a professional cybercrime group to dredge up some useful documents to hawk to the highest bidder.