Microsoft is issuing an emergency fix to close off a vulnerability in Microsoft’s SharePoint software that hackers have exploited to carry out widespread attacks on businesses and at least some federal agencies.

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

A cyber-espionage campaign centered on vulnerable versions of Microsoft's server software now involves the deployment of ransomware, Microsoft said in a late Wednesday blog post.

Federal cybersecurity officials have issued a warning to Microsoft users about a security flaw allowing hackers to access to certain SharePoint systems.

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 security patch Microsoft released this month failed to fully fix a critical flaw in the U.S. tech giant's SharePoint server software, opening the door to a sweeping global cyber espionage effort, a timeline reviewed by Reuters shows.

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.

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