Microsoft executive emails hacked by Russian intelligence group, company says

Microsoft said in a Friday regulatory filing that a Russian intelligence group accessed some of the software maker's top executives' email accounts. Nobelium, the same group that breached government supplier SolarWinds in 2020, carried out the attack, which Microsoft detected last week, according to the company.

The announcement comes after new U.S. requirements for disclosing cybersecurity incidents went into effect. A Microsoft spokesperson said that while the company does not believe the attack had a material impact, it still wanted to honor the spirit of the rules.

In late November, the group accessed "a legacy non-production test tenant account and gain a foothold, and then used the account's permissions to access a very small percentage of Microsoft corporate email accounts, including members of our senior leadership team and employees in our cybersecurity, legal, and other functions, and exfiltrated some emails and attached documents," Microsoft's Security Response Center wrote in the blog post.

The company's senior leadership team, including finance chief Amy Hood and president Brad Smith, regularly meets with CEO Satya Nadella.

Microsoft said it has not found signs that Nobelium had accessed customer data, production systems or proprietary source code.

The Cybersecurity and Infrastructure Security Agency did not immediately respond to a request for comment.

Microsoft and the U.S. government consider Nobelium to be a part of the Russian foreign intelligence service SVR. The hacking group was responsible for one of the most prolific breaches in U.S. history when it added malicious code to updates to SolarWinds' Orion software, which some U.S. government agencies were using. Microsoft itself was ensnared in the hack.

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