Who was blamed for NotPetya in February 2018?

Who was behind the NotPetya malware that struck Ukraine in 2017? On 15 February 2018, the United Kingdom government and the United States White House gave their answer: the Russian military.

Both governments accused it of being responsible for launching NotPetya in June 2017. The White House described the incident as the most destructive and costly cyberattack in history. It said Russia would face "international consequences", without specifying what they would be.

Russia denied responsibility. It dismissed the accusation as "groundless", said it lacked evidence, and called it "Russophobic".

The attack being referred to

The attacks used Petya-based malware and began on 27 June 2017. They swamped the websites of Ukrainian organisations, including banks, ministries, newspapers and electricity firms. Similar infections were reported in France, Germany, Italy, Poland, Russia, the United Kingdom, the United States and Australia.

ESET estimated on 28 June 2017 that 80% of all infections were in Ukraine, with Germany second hardest hit at about 9%. The Ukrainian government said that day that the attack had been halted. By 30 June 2017, the Associated Press reported that experts agreed the malware had been masquerading as ransomware, while actually being designed to cause maximum damage, with Ukraine as its main target.

The public attribution on 15 February 2018 thus tied the Russian military to an attack whose heaviest damage had fallen on Ukraine.