Hackers accessed controls at more than 30 Minnesota water systems

9 min read

A coordinated cyberattack on July 26–27 targeted operational technology at more than 30 Minnesota water and wastewater systems, affecting automated controls, communications and at least one plant that went briefly offline. Crews used stored water, manual operations and contingency procedures to maintain service, and officials reported no known drinking water quality impact. Investigators have not confirmed attribution, though a preliminary suspicion of Iranian‑affiliated actors was reported; federal agencies including CISA and state cybersecurity teams are investigating. The incident highlights widespread internet exposure of programmable controllers, uneven utility cybersecurity capacity, and recent federal guidance urging isolation of vital OT systems.

Attackers reached controls at more than 30 Minnesota water systems