The attack, which targeted the water supply in Oldsmar, a small city in Florida, was discovered by staff at the plant — they noticed the mouse moving on the screen — and they rushed to take action before any damage was caused.

The attackers breached the facility via TeamViewer, which staff had been using to monitor systems remotely and respond to issues related to the water treatment process. The computers at the plant were running Windows 7 and all devices used the same password for remote access. Computers were remotely accessible from the internet and were not protected with firewalls, making it easier for the hackers to gain access.