BOSTON — A Russian man whom US prosecutors say previously worked for Russia's Federal Security Service (FSB) intelligence agency pleaded not guilty on Thursday to a charge that he participated in a cyber espionage campaign that a technology company conducted against Western organisations.
Denis Obrezko, who was extradited last month from Thailand following his arrest there in November, pleaded not guilty during a brief virtual hearing before a federal magistrate judge in Boston after being indicted earlier this week for conspiring to commit computer fraud and abuse.
The 36-year-old was charged over what the indictment alleges was a Russian government-linked cyber espionage campaign that targeted US and European companies, European government agencies aligned with North Atlantic Treaty Organisation (Nato) and organisations supporting Ukraine's resistance to Russia's invasion.
The indictment said cybersecurity researchers tracked the hacking operations, which were dubbed "Void Blizzard" and "Laundry Bear," the same names that Microsoft and Dutch intelligence agencies cited in May 2025 when describing a newly identified Russian cyber group.
Obrezko faces a maximum sentence of 10 years in prison if convicted.
His lawyer, Max Nemtsev, in an email said he plans "to vigorously contest the charges on both factual and legal grounds." According to the indictment, Obrezko had worked at Russia's FSB from 2012 to 2017 before joining technology firm Yutek-NN, where he was a deputy director.
The indictment said that the company conducted cyber espionage campaigns at the behest of the Russian government. Yutek could not be reached for comment.
The indictment said Obrezko and other employees and associates of Yutek conspired since at least 2023 to extract email and other data from companies' systems using tools like fake domain names, VPNs and proxy servers.
Victims included a social media network; a US development company; a cloud software company; and a US-based educational institution. Court filings say the Federal Bureau of Investigation (FBI) has identified at least 11 US companies that have been hacked, a number it believes to be just a fraction of Void Blizzard's victims.
According to the indictment, Obrezko's phone also stored a file containing AI-generated summaries of more than 13,000 stolen emails from members of an Eastern European parliament.
After Microsoft in May 2025 published a report detailing the activities of Void Blizzard, Obrezko corresponded with an unnamed co-conspirator who went by the alias "Ethan Hunt," the same name as the character Tom Cruise plays in the Mission: Impossible movie franchise, the indictment said.
