No

A cyber attack is a cyber operation, whether offensive or defensive, that is reasonably expected to cause injury or death to persons or damage or destruction to objects.

Michael Schmitt et al; Tallinn Manual 1.0, pp 92
  • Cyber Operation?
  • Expected to cause death or injury to people or damage to objects?
US Operations to “Prepare the Battlefield” for Potential Future Operations Against the Russian Power Grid, If Necessary does not match this definition. Here's a list of actual cyberattacks and and why this matters.

What happened?

U.S. officials reveal ongoing efforts to deploy hacking tools against Russian grid systems as a deterrent and warning to Russia