Deserialization Vulnerability in Microsoft Office SharePoint
CVE-2026-45659

8.8HIGH

Key Information:

Vendor

Microsoft
Status
Microsoft Sharepoint Enterprise Server 2016
Microsoft Sharepoint Server 2019
Microsoft Sharepoint Server Subscription Edition
Vendor
CVE Published:
22 May 2026

What is CVE-2026-45659?

A vulnerability in Microsoft Office SharePoint permits an authorized attacker to exploit deserialization weaknesses in the software. This allows unauthorized code execution over a network, potentially compromising the integrity and availability of the affected system. Timely patching is essential to mitigate risks associated with this vulnerability.

Affected Version(s)

Microsoft SharePoint Enterprise Server 2016 x64-based Systems 16.0.0 < 16.0.5552.1002

Microsoft SharePoint Server 2019 x64-based Systems 16.0.0 < 16.0.10417.20128

Microsoft SharePoint Server Subscription Edition x64-based Systems 16.0.0 < 16.0.19725.20280

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

.