At least two Chinese hacking groups were using security flaws in SharePoint, a popular collaboration software, to breach systems, Microsoft said.

Chinese "threat actors" have hacked Microsoft's SharePoint document software servers and targeted the data of the businesses using it, the firm has said. China state-backed Linen Typhoon and Violet Typhoon as well as China-based Storm-2603 were said to have "exploited vulnerabilities" in on-premises SharePoint servers,

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