CISA released an urgent message warning water utilities to disconnect their logic controllers from the internet in the face of rising cyberattacks.

The hacks target internet-facing programmable logic controllers (PLCs) that control equipment and allow machinery to communicate. They monitor and control the water pressure, chemical dosing, and other factors to ensure the water is safe.

Many of the PLCs are apparently open to the internet and use default credentials, allowing a remote attacker to easily take them over.

I assume it is this CISA: https://en.wikipedia.org/wiki/Cybersecurity_and_Infrastructure_Security_Agency