Operation "Armageddon", 2013[1] Operation "Snake", February 2014[5][6][7] Attacks on the automated system "Elections", June 2014[8] Ukraine power grid hack, December 2015. Attacks using the Trojan virus BlackEnergy on energy companies in Ukraine which provide energy to Kyiv, Ivano-Frankivsk and Chernivtsi regions[9][10] This was the first successful cyber attack on a power grid.[9] Second Ukraine power grid hack, December 2016.[11][12] Paralysis of the State Treasury of Ukraine, December 2016[13][14] 2017 cyberattacks on Ukraine, Mass hacker supply-chain attack, June 2017 using Petya virus[15] According to the US Presidential Administration, this attack became the largest known hacker attack.[16] 2022 Ukraine cyberattack, attacks on Ukrainian government websites, January 2022, one day after US-Russian negotiations on Ukraine’s future in NATO failed.[17][18] Attacks in February 2022, after Russian troops invaded eastern regions of Ukraine, took down several major Ukrainian governmental and banking websites. U.S. intelligence attributed the attacks to Russian attackers, although the Russian government denied involvement.[19]