CVE-2026-45659: high-severity vulnerability in Microsoft SharePoint Enterprise Server 2016
Microsoft SharePoint Remote Code Execution Vulnerability
Published · Updated
Prioritize patching. It under exploitation confirmed by CISA and has a public proof of concept.
Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
Microsoft SharePoint has a flaw that allows an authorized user to run malicious code on the server by sending specially crafted data. This is dangerous because it gives attackers complete control over the SharePoint system.
CWE-502 deserialization vulnerability in SharePoint processes untrusted serialized objects from authenticated users, allowing arbitrary code execution with server privileges. Attack requires valid credentials and network access to the affected SharePoint instance.
The full analysis of this CVE is available in Portuguese →
In the same product, most dangerous first.