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
I worked on new SCADA for a water company across all theirs sites. Previously they were a mismatch of different systems and all airgapped.
They standardised everything and put them all on VPN. Suddenly you could access the secure water treatment works with 24/7 security guards and the control room was a bunker, from the unmanned rural sewage works with a portacabin for the server, the key hidden under a brick, and wifi for the PLCs.
The sewage works had always operated like that because it was deemed low risk. No one considered the VPN changed the threat model.