Amid a series of cyberattacks affecting water systems across the country, U.S. government security agencies warned that hackers are actively accessing Siemens devices used in critical infrastructure.
The Cybersecurity and Infrastructure Security Agency (CISA), the FBI, and the National Security Agency, among others, noted that the attackers are targeting “all” Siemens S7 programmable logic controllers. These devices are used to manage automated physical processes in energy, water systems, manufacturing, and agriculture.
According to CISA, the attacks are part of a broader activity aimed at water supplies and wastewater systems in the United States. The agency warned that the disruption could lead to downtime, security incidents, or damage to essential infrastructure equipment that relies on these devices.
The agencies explained that hackers are using artificial intelligence to generate exploitation scripts. These are based on publicly available information to detect and exploit programmable logic controllers running outdated software or that are poorly protected.

Previous Warnings and Rural Communities
CISA has been warning critical infrastructure owners for some time about the need to keep these devices disconnected from the internet. Officials acknowledged that rural communities are often the most affected, as these systems cover extensive geographic areas.
An incident response professional working with critical infrastructure told TechCrunch that the use of artificial intelligence by attackers to identify and target vulnerable controllers, as well as to understand how these devices operate, is striking. However, he warned that these devices are already highly vulnerable in themselves.
This is the latest warning from CISA following a series of cyberattacks attributed to hackers suspected of Iranian origin who have targeted water and wastewater providers in the United States in recent months.
The agency indicated that the attacks have intensified since these groups began targeting internet-connected systems used in critical infrastructure.
Reported Intrusions in Several States
Officials from various parts of the country reported intrusions at water facilities in Minnesota and Michigan, as well as in Arkansas, Georgia, and New Jersey.