The U.S. Department of Justice said Thursday that two U.S.-based law firms were among the victims of a “complex transnational organized cyber-crime network” that has been taken down thanks to a law enforcement effort involving cooperation between U.S. and European officials. 

The DOJ's statement did not specify the names of the entities, only that one was a law firm located in Washington, D.C., and another was a law office in Wellesley, Massachusetts.

The hackers were using the GozNym malware, which is designed to capture online banking login credentials. The hackers then gain access to bank accounts and steal money from victims by laundering those funds through U.S. and foreign beneficiary bank accounts controlled by the hackers. All in all, the group was hoping to make out with more than $100 million, the DOJ said.

This isn't the first time that law firms have been the targets of cyber attacks—and it likely won't be the last. The American Lawyer reported in January that an unnamed U.S. firm had been hacked by the Chinese government-sponsored group called APT10 between November 2017 and September 2018.

A study conducted by IBM in 2018 found that it takes about six months to discover that a breach has occurred, and then an average of 69 days to contain the breach. Law firms, because of the sensitive information they possess regarding their various clients, are a very attractive target for those looking to obtain data to sell or expose. By hacking one system, attackers can get information on potentially hundreds of companies and individuals.

According to the indictment, Alexander Konovolov, aka “NoNe” and “none_1,” of Tbilisi, Georgia, was the organizer and leader of the GozNym network that controlled about 41,000 victim computers infected with the malware.

U.S. Attorney Scott W. Brady of the Western District of Pennsylvania made the announcement of the indictments at Europol in The Hague, Netherlands.

“International law enforcement has recognized that the only way to truly disrupt and defeat transnational, anonymized networks is to do so in partnership,” Brady said. “The collaborative and simultaneous prosecution of the members of the GozNym criminal conspiracy in four countries represents a paradigm shift in how we investigate and prosecute cybercrime. Cybercrime victimizes people all over the world. This prosecution represents an international cooperative effort to bring cybercriminals to justice.”

The defendants reside in Russia, Georgia, Ukraine, Moldova and Bulgaria. Without the hope of extradition to the United States, five of the hackers who reside in Russia remain at large.

The case is being prosecuted by Assistant U.S. Attorney Charles A. “Tod” Eberle, the chief of national security and cybercrime for the Western District of Pennsylvania.