The secret scanning tool rocked the tech world and that of privacy and anti-surveillance activists this week, shocked by how broad the request was, and the fact that it had kept under wraps. Until Reuters reported its existence this week, the tool remained a secret not just to the public, but also to most people at Yahoo, including the security team, which caught it and thought it was a sophisticated and dangerous piece of malware installed by hackers, as reported by Motherboard on Friday.

In an age where the FBI asked Apple to unlock the iPhone of a dead terrorist, and countless top secret documents revealed the vast surveillance powers of the NSA, asking Yahoo to use a scanning tool that former employees defined as a "buggy" and a "poorly designed" "backdoor" or "rootkit," was an unusual request as it wasn't targeted—Yahoo was essentially looking through the whole haystack looking for a few needles—and the company apparently didn't fight back.