The network unraveled after the arrest of hacker Peter Yuryevich Levashov in Spain over the weekend.
The U.S. Justice Department said on Monday it had launched an effort to disrupt and dismantle the Kelihos botnet, a global network of tens of thousands of infected computers allegedly operated by a Russian cybercriminal who was arrested in Spain over the weekend.
Kelihos malware targeted computers running Microsoft’s Windows operating system, the department said in a statement. According to the civil complaint, Peter Yuryevich Levashov, a Russian citizen, allegedly operated the Kelihos botnet since approximately 2010, the statement added.
Levashov was arrested in Spain over the weekend while reportedly on vacation with his family.
Russian-state media service RT reported, citing his wife, that Levashov was suspected of being connected to hacking attacks linked to alleged interference in last year’s U.S. election, which intelligence agencies in Washington have concluded were carried out by the Russian government in order to help President Donald Trump win.
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But a U.S. Justice Department official told reporters Monday that past indictments against Levashov for alleged cyber crimes, and the current action against Kelihos, were not related to election hacking.
The Kelihos botnet has been a source of criminal activity targeting computer users worldwide since at least 2010, the official said. It has been involved in various spam attacks, including pump-and-dump schemes, password thefts and injecting various forms of malware, including ransomware, into target devices.
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In order to liberate the victim computers, the United States obtained court orders to take measures to neutralize the Kelihos botnet, including establishing substitute servers and blocking commands sent from the botnet operator, the department said.