Heap-based buffer overflow in Microsoft SharePoint Server - CVE-2026-88155
Published: October 14, 2026
Vulnerability identifier: #VU155350
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-2026-88155
CWE-ID: CWE-122
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to execute arbitrary code.
The vulnerability exists due to a heap-based buffer overflow in Microsoft Office SharePoint when handling network-based operations. A remote user can trigger the buffer overflow over the network to execute arbitrary code.
Exploitation requires Manage List permissions. The Preview Pane is not an attack vector.
Affected software
Microsoft SharePoint Server
How to mitigate CVE-2026-88155
Install security update from vendor's website.
Microsoft SharePoint Server - update to 16.0.20326.20190