In fact, of all the countries afflicted in the first wave of the spread of the malicious software, Russia was hit the hardest: The virus tried to infect more computers in Russia than anywhere else, according to an analysis by Kaspersky Lab, a Russian antivirus company.
A spokeswoman for the ministry, Irina Volk, told Russian news agencies that key servers had been unaffected because they were running domestic software, including a little-known operating system called Elbrus, first developed in the late Soviet period.
In December, the Obama administration imposed sanctions on the Russian hacker associated with Gameover Zeus, Evgeniy M.
Mikhail Delyagin, the director of the Institute of Problems of Globalization in Russia, said he suspected the United States government was behind the WannaCry attack, saying it could be the retaliation the Americans threatened against Russia for its hacking efforts last year.
An earlier version of this article misstated part of the name of the agency that the malware used in a global cyberattack was stolen from.