Chinese Threat Actors Exploit ToolShell SharePoint Flaw Weeks After Microsoft's July Patch
Oct 22, 2025
Cyber Espionage / Vulnerability
Threat actors with ties to China exploited the ToolShell security vulnerability in Microsoft SharePoint to breach a telecommunications company in the Middle East after it was publicly disclosed and patched in July 2025. Also targeted were government departments in an African country, as well as government agencies in South America, a university in the U.S., as well as likely a state technology agency in an African country, a government department in the Middle East, and a finance company in a European country. According to Broadcom's Symantec Threat Hunter Team, the attacks involved the exploitation of CVE-2025-53770 , a now-patched security flaw in on-premise SharePoint servers that could be used to bypass authentication and achieve remote code execution. CVE-2025-53770, assessed to be a patch bypass for CVE-2025-49704 and CVE-2025-49706, has been weaponized as a zero-day by three Chinese threat groups , including Linen Typhoon (aka Budworm), Violet Typhoon (aka Sheathminer)...