A Russian national has been sentenced to over four years in prison after pleading guilty to conspiring to commit computer fraud by developing the notorious Citadel banking malware.
Dimitry Belorossov, 22, of Saint Petersburg, who operated under the alias Rainerfox, pleaded guilty in 2014 to distributing and installing Citadel, which was designed to steal financial information including credit card data and customer records.
The sophisticated banking trojan was first spotted in 2011 and worked by creating an infected botnet of computers, which cyber criminals then exploited via remote access.
Citadel infected up to 11 million computers worldwide and was responsible for over $500m in losses. The FBI said that Belorossov controlled a 7,000-strong botnet at its peak.
Belorossov was eventually tracked down and arrested in Spain last year before being extradited to the US. The criminal action was brought forward by the US Attorney's Office in the northern district of Georgia after it was found that at least one infected computer system was located in the region.
The FBI explained that Belorossov provided "online assistance" with developing improvements and alterations to Citadel by posting on an underground hacker forum.
"In 2012 Belorossov made numerous postings to Citadelmovement.com, an online forum in which Belorossov discussed his Citadel botnet and recommended improvements to the Citadel malware," the agency said.
"In those postings, which were in Russian, Belorossov shared his concurrence with the improvements to Citadel recommended by others and commented on the efficacy of additional criminal functions other customers had recommended as enhancements to the Citadel malware."
Belorossov will face three years of supervised release after his jail sentence, and must pay over £300,000 in restitution.
John Horn, US attorney for the northern district of Georgia, said that fighting cybercrime now needs a global response.
"This defendant committed computer hacking offences on victims in the US from the relative safety of his home country of Russia, but he was arrested by our law enforcement partners in Spain," he added.
"As malware and hacking toolkits continue to victimise computer users around the world, we will step up our efforts to focus internationally on the criminals who develop these programs."
J Britt Johnson, special agent in charge of the FBI Atlanta field office, reinforced the idea that cybercrime, no matter where it originates, is open to prosecution.
"The FBI, in working with its international partners, continues to demonstrate that international boundaries no longer provide a safe haven for cyber criminals targeting US individuals or interests domestically," he said.
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