Microsoft Corp. accused Chinese state-sponsored hackers of using flaws in its SharePoint document management software in a hacking campaign that has targeted businesses and government agencies around the world.

The tech giants have evidence that Chinese hackers are exploiting the new bug, but warned "multiple actors" are also hacking into affected SharePoint systems.

The company uncovers evidence that at least three China-based hacking groups are abusing the zero-day flaw in SharePoint software to access servers.