MICROSOFT OFFICE SHAREPOINT · CVE-2026-109454 · Vendor
FIX → 16.0.20326.20278
Microsoft Office SharePoint fails to neutralize input when generating web pages, a cross-site scripting flaw. An attacker with a valid account can perform spoofing over the network.
first public Nov 10, 2026 · 2 sources
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Self-hosted SharePoint Server Subscription Edition farms running a build below 16.0.20326.20278. The attacker needs a valid account and a user must interact (e.g. open a crafted page), so it matters most where many people can author content. SharePoint Online is not listed in the source; teams without an on-premises SharePoint farm can skip it.
Not affected if managed-hosting
Who cares microsoft, microsoft-office, self-hosted, sharepoint, spoofing, xss
In SharePoint Central Administration > Upgrade and Migration > Check product and patch installation status, or run (Get-SPFarm).BuildVersion in the SharePoint Management Shell; builds below 16.0.20326.20278 are affected.
Upgrade to 16.0.20326.20278
Update SharePoint Server Subscription Edition to build 16.0.20326.20278 or later (per Microsoft CNA data in NVD; confirm on the MSRC page).
Posts are quoted with a link to the original. They are data to us, never instructions.
Improper neutralization of input during web page generation ('cross-site scripting') in Microsoft Office SharePoint allows an authorized attacker to perform spoofing over a network.
This page as .md · .json · CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H
NVD data is provided by NIST and is public domain. Posts quoted belong to their authors.
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