But many of the attacks were thwarted, or there was enough redundancy built into the Ukrainian networks that the efforts did little damage. The result, Mr. Smith said, is that the attacks have been underreported.
In many instances, Russia coordinated its use of cyberweapons with conventional attacks, including taking down the computer network of a nuclear power plant before moving in its troops to take it over, Mr. Smith said. Microsoft officials declined to identify which plant Mr. Smith was referring to.
While much of Russia’s cyberactivity has focused on Ukraine, Microsoft has detected 128 network intrusions in 42 countries. Of the 29 percent of Russian attacks that have successfully penetrated a network, Microsoft concluded, only a quarter of those resulted in data being stolen.
Outside Ukraine, Russia has concentrated its attacks on the United States, Poland and two aspiring members of NATO, Sweden and Finland. Other alliance members were also targeted, especially as they began to supply Ukraine with more arms. Those breaches, though, have been limited to surveillance — indicating that Moscow is trying to avoid bringing NATO nations directly into the fight through cyberattacks, much as it is refraining from physical attacks on those countries.
But Microsoft, other technology companies and government officials have said that Russia has paired those infiltration attempts with a broad effort to deliver propaganda around the world.
Microsoft tracked the growth in consumption of Russian propaganda in the United States in the first weeks of the year. It peaked at 82 percent right before the Feb. 24 invasion of Ukraine, with 60 million to 80 million monthly page views. That figure, Microsoft said, rivaled page views on the biggest traditional media sites in the United States.