The massive data breach that struck Target over the holiday shopping season may have been part of a larger, unprecedented attack on U.S. retailers by Russian hackers, according to a new report by cyber security firm iSIGHT Partners and the U.S. Secret Service. The Associated Press explains that the malicious software hackers used to steal personal customer data from retailers point of sales systems is almost certainly derived from BlackPOS software, which uses malware script from Russia.