Probe of NSA Hacking Focuses on Tools Left on Remote Computer

A U.S. investigation into a leak of hacking tools used by the National Security Agency is focusing on a theory that one of its operatives carelessly left them available on a remote computer and Russian hackers found them, four people with direct knowledge of the probe told Reuters. The tools, which enable hackers to exploit software flaws in computer and communications systems from vendors such as Cisco Systems and Fortinet Inc, were dumped onto public websites last month by a group calling itself Shadow Brokers.