If exploited, attackers can gain full access to SharePoint content and potentially pivot to Outlook, Teams, and OneDrive. Learn how to protect your SharePoint server from compromise.

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.

The attacks, discovered over the weekend, exploit a previously unknown vulnerability in the document-sharing software, prompting immediate action from both Microsoft and federal investigators. Newsweek reached out to Microsoft and the Cybersecurity and Infrastructure Security Agency (CISA) via email for comment.