Missing Authorization in Microsoft SharePoint Server Subscription Edition - CVE-2026-88164
Published: October 14, 2026
Vulnerability identifier: #VU155783
CSH Severity: Low
CVSS v4: 5.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-88164
CWE-ID: CWE-862
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to escalate privileges.
The vulnerability exists due to missing authorization in Microsoft Office SharePoint when handling requests. A remote user can send a specially crafted request to perform operations beyond their account permissions to escalate privileges.
No additional user interaction is required. The Preview Pane is not an attack vector.
Affected software
Microsoft SharePoint Server Subscription Edition
How to mitigate CVE-2026-88164
Install security update from vendor's website.
Microsoft SharePoint Server Subscription Edition - update to 16.0.20326.20190