Targets have included the computers of the Democratic National Committee in 2015 and the tech supplier SolarWinds, which allowed Russia to gain access to systems at the State Department, the Department of Homeland Security and parts of the Pentagon in 2020. Microsoft called that incident “the most sophisticated nation-state cyberattack in history.”
The method used in the new hack appears to be less exotic — a relatively basic tactic known as password spraying, in which hackers try common passwords on a vast array of accounts. The group, which has been known to use this tactic, found an opening in an old account for a testing system, and then used that account’s permissions to gain access to the corporate email accounts, Microsoft said.
“To date, there is no evidence that the threat actor had any access to customer environments, production systems, source code or A.I. systems,” Microsoft said in a statement.
The regulatory filing said the company had notified and was working with law enforcement.
Microsoft, which supplies technology to many Western governments, has long been the target of nation-state hacking. Last year, Chinese hackers breached Microsoft’s systems and gained access to the email accounts of Commerce Secretary Gina M. Raimondo and other government officials.
