Deserialization of Untrusted Data in Microsoft SharePoint Server - CVE-2026-109464
Published: November 10, 2026
Vulnerability identifier: #VU164735
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-109464
CWE-ID: CWE-502
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to execute arbitrary code on the affected SharePoint server.
The vulnerability exists due to deserialization of untrusted data in Microsoft SharePoint Server when processing specially crafted requests. A remote user can send a specially crafted request to execute arbitrary code on the server.
Affected software
Microsoft SharePoint Server
How to mitigate CVE-2026-109464
Install security update from vendor's website.
Microsoft SharePoint Server - update to 16.0.20326.20278