Researchers say Chinese actors, along with other criminal hackers, exploited a security flaw in SharePoint software widely used by governments and businesses.

At least three China-based hacking teams have been exploiting a previously unknown flaw in Microsoft SharePoint since at least July 7, the company said in a blog post. Why it matters: Microsoft and security researchers didn't uncover the vulnerability until this past weekend,

It's not just data theft. A China-based hacking group is using a flaw in vulnerable SharePoint servers to deliver ransomware, Microsoft warns.