https://arstechnica.com/information-technology/2020/12/microsoft-is-reportedly-added-to-the-growing-list-of-victims-in-solarwinds-hack/

Microsoft was hacked by the same group that compromised the networks of software maker SolarWinds and multiple federal agencies, Reuters reported, citing people familiar with the matter.

Citing the same people, the news service said that Microsoft’s own products were then used in follow-on hacks against others. It wasn’t immediately clear how many Microsoft users were affected or what Microsoft products were used. Microsoft representatives weren’t immediately available for comment.