A cyberattack happened in the Ukrainian capital Kyiv just before midnight on 17 December 2016, and lasted for just over an hour.
[1][2] The national electricity transmission operator Ukrenergo said that the attack had cut one fifth of the city's power consumption at that time of night.
[3] A security flaw meant that a single packet could put the relays in a state where it would be useless unless manually rebooted.
[3] Evidence from logs obtained by Dragos Security showed the attackers initially opened every circuit breaker in the transmission station, causing a power cut.
[3] In April 2022, Ukrainian authorities announced that they had prevented a cyberattack that used malware similar to Industroyer.