"Oprea essentially wreaked havoc on Subway, both at the corporate level and at the individual franchise level," prosecutors wrote in their sentencing memorandum. Subway, they say, spent more than $5 million to investigate the source of the data leaks and make changes to its computer systems.
The two men pleaded guilty to hacking into the "point-of-sale" systems that link merchants' computers to credit card payment companies.
Once he hacked into the point-of-sale systems, prosecutors said, Oprea installed keystroke logging software to record credit card payment data and imported that information to computer "dump sites" he set up in the U.S. and Cyprus. He would use the stolen credit card data to make purchases for himself and sold some of it on the black market.
"These cyber criminals are very clever and have the ability to reach into American commerce from half a world away," Kacavas said.
Dolan's role, prosecutors said, was to identify vulnerable merchant systems that had certain remote desktop software applications installed on them. Among Dolan's targets was the Plaistow Subway, where he stole the credit card information for hundreds of customers.
During the latter stages of their scheme, prosecutors said, Secret Service agents were able to monitor their exploits and to notify banks that issued the compromised cards before the credit card info could be abused.
Oprea supervised various sellers of the stolen credit card data, including Cezar Butu, who worked with a team of crooks in a rented house in Lille, France, to encode the stolen data onto blank plastic cards. Butu was sentenced in January to two years in prison.