Incorrect authorization in Microsoft SharePoint Server - CVE-2026-123391
Published: November 11, 2026
Vulnerability identifier: #VU165486
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-2026-123391
CWE-ID: CWE-863
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to escalate privileges and modify protected content or administrative configuration.
The vulnerability exists due to incorrect authorization in Microsoft SharePoint Server when handling requests. A remote user can send a specially crafted request to perform operations beyond the permissions granted to their account to escalate privileges and modify protected content or administrative configuration.
Affected software
Microsoft SharePoint Server
How to mitigate CVE-2026-123391
Install security update from vendor's website.
Microsoft SharePoint Server - update to 16.0.20326.20136