U.S. authorities said they have seized dozens of website domain names that hackers linked to Russian intelligence allegedly used to try and break into U.S. government computer systems.
The October 4 announcement was the latest in a string of moves by United States and other Western governments seeking to choke out what they say is a wide-ranging cyber campaign by Russian hackers, many of whom are state-sponsored.
More than 100 website domain names associated with the hackеrs, known as the Callisto Group, were seized, the Justice Department said in a statement, an action that was coordinated with tech giant Microsoft. A domain name is roughly the series of numbers on a website that allows the website to communicate with servers and send and receive information.
U.S. officials said the group sent e-mails that that appeared to come from a trusted source to scores of people, including former U.S. military and intelligence employees, as well as NGOs, U.S. companies, and others.
SEE ALSO: How An Accused Russian Spy Traversed Nagorno-Karabakh And Armenian Politics As A Journalist"This seizure is part of a coordinated response with our private sector partners to dismantle the infrastructure that cyberespionage actors use to attack U.S. and international targets," said U.S. Attorney Ismail J. Ramsey for the Northern District of California.
Known as spear phishing, the tactic involves sending e-mails with links or attachments that contain malicious computer code. The recipients are tricked into opening the attachments or clicking on the links, launching code that allows hackers to burrow into the computer systems either to steal information or simply observe communications.
Callisto Group is the name given by Western officials and tech researchers to the Russian Federal Security Service's Center for Information Security, or Center 18. The center is one of at least two that conduct cyberoperations for the service, known as the FSB.
Other Russian security agencies, including the main military intelligence agency known as the GRU, or the Foreign Intelligence Service, known as the SVR, also run similar operations.
In its statement announcing the seizure of 66 domain names, Microsoft said the group, which it called Star Blizzard, said detailed research on targets was carried out before sending spear phishing e-mails. Among the U.S. government agencies Star Blizzard targeted was the U.S. Department of Energy, which oversees many nuclear programs.
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Last December, U.S. prosecutors charged an FSB officer and another Russian man of being part of Callisto Group's spear phishing campaign.
The FSB's Center 18 was roiled by a major treason scandal in 2019, when two of its top officers were convicted of state treason for passing classified intelligence to Western authorities. The center had previously cooperated regularly with the U.S. Justice Department on joint efforts to investigate cybercrimes.
The FSB’s other main cyber unit, Center 16, or the Center for Radio-Electronic Intelligence by Means of Communication, oversees the FSB's signals intelligence capabilities: intercepting communications, decryption, and data processing.
Last year, Western authorities announced they had effectively unplugged a powerful surveillance tool the center had used for more than a decade to burrow into computer servers in more than 50 countries.