Hackers believed to operate out of Eastern Europe hacked dozens of companies and government agencies on at least four continents by breaking into a single product they all used. The victims include New Zealands central bank, Harvard Business School, Australias securities regulator, the high-powered U.S. law firm Jones Day whose clients include former President Donald Trump the rail freight company CSX and the Kroger supermarket and pharmacy chain. The two-stage mega-hack in December and January of a popular file-transfer program from the Silicon Valley company Accellion highlights a threat that security experts fear may be getting out of hand.”]