CVE-2026-123390 · Vendor
NO FIX YET
Microsoft SharePoint mishandles untrusted serialized data, so an attacker with a valid account can run code over the network. NVD rates it high (CVSS 8.8).
first public Nov 10, 2026 · 1 source
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Organizations running Microsoft SharePoint Server on premises, where an authorized user can reach the affected deserialization path over the network. The sources do not name specific versions, configurations or SharePoint Online status. Teams using only SharePoint Online can likely skip it, but the sources do not confirm this.
Not affected if sharepoint-online
Who cares microsoft-office, on-premises, sharepoint
No fix yet, per the sources.
Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.
This page as .md · .json · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/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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