The documents were littered with NSA claims that the agency's hackers had access to nearly every piece of commercial hardware and software on the market. The agency appeared to have acquired a vast library of ways into every major app, social media platform, server, router, firewall, antivirus software, iPhone, Android, BlackBerry, computer, and operating system. In the hacking world, these invisible entry points have sci-fi names: they call them zero-days.
