A former NSA employee carelessly left those hacking tools on a remote server three years ago after an operation and a group of Russian hackers found them. Instead of warning the affected companies that their customers were at risk, the NSA maintained the silence. The leak of NSA’s hacking tools, which enable hackers to exploit vulnerabilities in systems from big vendors like Cisco Systems, Juniper, and Fortinet, were dumped publicly online by the group calling itself ” The Shadow Brokers” Shortly after the initial leak, firewall vendors Cisco and Fortet confirmed that the leaked vulnerabilities were legitimate and issued out patches to fix those exploits.
Source: https://thehackernews.com/2016/09/nsa-hacking-tool-exploits.html