Mirai botnet caused a massive cyberattack n 2016, that took down major sites like Twitter and Netflix.

Three students created Mirai, which infected Internet of Things devices (cameras, routers), turning them into "bots" that flooded sites with traffic, causing them to crash. Originally developed to gain an advantage in Minecraft, the botnet quickly spiraled out of control. The students were caught, and since then, they have been helping the FBI catch "real" cybercriminals.