A Ukrainian man charged last year with conducting one of the most severe ransomware attacks against U.S. targets has been extradited to the United States and made a court appearance Wednesday, the U.S. Justice Department said.

According to an August 2021 indictment, Yaroslav Vasinskyi accessed the internal computer networks of several victim companies and deployed Sodinokibi/REvil ransomware to encrypt the data on their computers, the Justice Department said in a statement.

Vasinskyi was allegedly responsible for the July 2021 ransomware attack against Florida software provider Kaseya, the department said.

Reuters could not reach a representative of Vasinskyi. Kaseya did not immediately return a message seeking comment.

The Ukrainian national was accused in the indictment of breaking into Kaseya over the July 4 weekend last year and simultaneously distributing with accomplices REvil ransomware to as many as 1,500 Kaseya customers, encrypting their data and forcing some to shut down for days, the Justice Department said.

While most of the 1,500 businesses paralyzed as a result around the globe faced limited concerns, the disruption was felt keenly in places such as Sweden, where hundreds of supermarkets had to close because their cash registers were inoperative, and New Zealand, where schools and kindergartens were knocked offline.

Vasinskyi was charged in the indictment with breaking into the victim companies and installing encryption software developed by the core REvil ransomware hacking group. REvil directly handled the ransom negotiations and split the profits with Vasinskyi and other affiliates. This model allowed the notorious ransomware gang to extort numerous companies for cryptocurrency.

Vasinskyi was arrested in Poland in October. The Justice Department charged him and a Russian late last year.

U.S. law enforcement authorities transported Vasinskyi to Dallas, Texas, where he arrived March 3, the Justice Department said Wednesday.

REvil was involved in an attack last year against top global meat processor JBS S.A.

Source: Voice of America