Microsoft contained a major SharePoint security flaw, amid fresh questions about the future of its legacy on-premises software.

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

A China-linked threat actor has been observed exploiting SharePoint servers to deliver ransomware, according to Microsoft researchers, in the latest sign of worsening attacks against on-premises SharePoint Server customers.

The name was coined by Dinh Ho Anh, a researcher from Khoa of Viettel Cyber Security, who developed the exploit. The researcher said he picked the name because it exploited ToolPane.aspx, a component for assembling the side panel view in the SharePoint user interface.

Microsoft has pointed the finger at three Chinese nation-state actors for exploiting the SharePoint vulnerabilities. Here's what we know about the security flaws and how to guard against future attacks.

Microsoft Corp. said a Chinese hacking group is exploiting security vulnerabilities in the company’s SharePoint servers to deploy ransomware, following a cyberattack discovered last week that has affected hundreds of entities around the world.