A first-of-its-kind cyberattack on the U.S. grid created blind spots at a grid control center and several small power generation sites in the western United States, according to a document posted yesterday from the North American Electric Reliability Corp.

The unprecedented cyber disruption this spring did not cause any blackouts, and none of the signal outages at the ”low-impact” control center lasted for longer than five minutes, NERC said in the ”Lesson Learned” document posted to the grid regulator’s website.

But the March 5 event was significant enough to spur the victim utility to report it to the Department of Energy, marking the first disruptive ”cyber event” on record for the U.S. power grid (Energywire, April 30).

The case offered a stark demonstration of the risks U.S. power utilities face as their critical control networks grow more digitized and interconnected — and more exposed to hackers. ”Have as few internet facing devices as possible,” NERC urged in its report.

The cyberattack struck at a challenging time for grid operators. Two months prior to the event, then-U.S. Director of National Intelligence Dan Coats warned that Russian hackers were capable of interrupting electricity ”for at least a few hours,” similar to cyberattacks on Ukrainian utilities in 2015 and 2016 that caused hourslong outages for about a quarter-million people.

Källa: SECURITY: Report reveals play-by-play of first U.S. grid cyberattack