CVE-2026-66805

Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-66805	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:microsoft:sharepoint_server:::::subscription:::*
	cpe:2.3:a:microsoft:sharepoint_server:2016::::enterprise:::
	cpe:2.3:a:microsoft:sharepoint_server:2019:::::::*

History

21 Oct 2026, 21:18

Type	Values Removed	Values Added
References	~~() https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-66805 - Vendor Advisory, Patch~~	() https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-66805 - Patch, Vendor Advisory

Information

Published : 2026-08-11 17:19

Updated : 2026-10-21 21:18

NVD link : CVE-2026-66805

Mitre link : CVE-2026-66805

CVE.ORG link : CVE-2026-66805

JSON object : View

Products Affected

microsoft

sharepoint_server

CWE

CWE-502

Deserialization of Untrusted Data

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