The Russian hackers, who worked for a shadowy state-sponsored group previously identified as Dragonfly or Energetic Bear, broke into supposedly secure, “air-gapped” or isolated networks owned by utilities with relative ease by first penetrating the networks of key vendors who had trusted relationships with the power companies, said officials at the Department of Homeland Security.
“They got to the point where they could have thrown switches” and disrupted power flows, said Jonathan Homer, chief of industrial-control-system analysis for DHS.
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