Chinese "threat actors" have hacked Microsoft's SharePoint document software servers and targeted the data of the businesses using it, the firm has said.

Microsoft said it identified 2 groups as leveraging flaws in SharePoint software; China said it firmly opposes all forms of cyberattacks.

In a blog post Tuesday, Microsoft said it observed hackers attempting to “gain initial access to target organizations.” According to Microsoft, those involved included hacking groups called Linen Typhoon and Violet Typhoon—which Microsoft said are linked to the Chinese government—and China-based group Storm-2603.