"In 2012 the Carna botnet was built and unleashed on the world. But it didn’t have any intentions on doing anything malicious. It was built just to help us all understand the Internet better. This botnet used the oldest security vulnerability in the book. And the data that came out of it was amazing.
The Carna botnet was used to scan the internet to create a map of where all the public facing computer are in the world. The map it created is remarkable."