Chinese hackers are exploiting a high-severity vulnerability in Microsoft SharePoint to steal data worldwide:

The vulnerability, tracked as CVE-2025-53770, carries a severity rating of 9.8 out of a possible 10. It gives unauthenticated remote access to SharePoint Servers exposed to the Internet. Starting Friday, researchers began warning of active exploitation of the vulnerability, which affects SharePoint Servers that infrastructure customers run in-house. Microsoft’s cloud-hosted SharePoint Online and Microsoft 365 are not affected.

Here’s Microsoft on patching instructions. Patching isn’t enough, as attackers have used the vulnerability to steal authentication credentials. It’s an absolute mess. CISA has more information. Also these four links. Two Slashdot threads.

This is an unfolding security mess, and quite the hacking coup.