Remote Code Execution Vulnerability in Microsoft SharePoint by Microsoft
CVE-2026-66808

8.8HIGH

Key Information:

Vendor

Microsoft
Status
Microsoft Sharepoint Enterprise Server 2016
Microsoft Sharepoint Server 2019
Microsoft Sharepoint Server Subscription Edition
Vendor
CVE Published:
11 August 2026

What is CVE-2026-66808?

A vulnerability exists in Microsoft Office SharePoint that allows an authorized attacker to exploit deserialization of untrusted data. This could enable the execution of arbitrary code over the network, potentially leading to unauthorized access and manipulation of sensitive data. To mitigate risks, users are urged to review the vendor's advisory and apply necessary security updates.

Affected Version(s)

Microsoft SharePoint Enterprise Server 2016 x64-based Systems 16.0.0 < 16.0.5565.1001

Microsoft SharePoint Server 2019 x64-based Systems 16.0.0 < 16.0.10417.20198

Microsoft SharePoint Server Subscription Edition x64-based Systems 16.0.0 < 16.0.19725.20522

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE...
vendor-advisorypatch

CVSS V3.1

Score:
8.8
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
Low
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.