Hackers cause power outages to close to 1/4 million people

March 19, 2021


On December 23, 2015, the Ukrainian Kyivoblenergo, a regional electricity distribution company, reported service outages to customers. The outages were due to a remote individual who took control of the operator workstation and opened breakers at 30 substations. At approximately 3:35 p.m local time, seven 110 kV and 23 35 kV substations were disconnected for three hours. The cyber attack impacted additional portions of the distribution grid and forced operators to switch to manual mode. The outages were originally thought to have affected approximately 80,000 customers, based on the Kyivoblenergo’s update to customers. However, later it was revealed that three different distribution oblenergos (a term used to describe an energy company) were attacked, resulting in several outages that caused approximately 225,000 customers to lose power across various areas. Shortly after the attack, Ukrainian government officials claimed the outages were caused by a cyber attack, and that Russian security services were responsible for the incidents.

Incident Date

December 23, 2015


Estimated Cost

No cost values disclosed.

Type of Malware

No Malware identified