CVE-2025-53770 and CVE-2025-53771 affecting Microsoft Sharepoint

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4:00pm, 21 July 2025

TLP Rating: Clear

CVE-2025-53770 and CVE-2025-53771 affecting Microsoft Sharepoint

CVE-2025-53770 & CVE-2025-53771 are variants of the existing vulnerabilities CVE-2025-49704 & CVE-2025-49706. This exploitation activity, publicly reported as “ToolShell”, provides unauthenticated access to systems and enables malicious actors full access to SharePoint content, including file systems, internal configurations, could allow code execution and persistent access through exfiltration of IIS machine keys. 

What's happening

Systems affected

On-premises SharePoint Servers.

What this means

On-premises SharePoint Servers exposed to the internet could be vulnerable to exploitation by remote unauthenticated attack.

What to look for

How to tell if you're at risk

On-premises Sharepoint servers exposed to the internet are at risk of being exploited.

How to tell if you're affected

What to do

More information

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