Department of Homeland Security headquarters, several of its agencies and the Department of Health and Human Services have been hacked as part of a wider breach of Microsoft SharePoint.​

The zero-day vulnerability — which was first disclosed late Saturday — has been exploited by several Chinese state-aligned groups, according to Microsoft.

Microsoft said some of the hackers involved in the cyberespionage sweep aimed at the U.S. tech giant's SharePoint servers are now using ransomware, a potential escalation in the wide-ranging spy campaign.