Cross-site scripting in Microsoft SharePoint Server - CVE-2026-102859
Published: October 13, 2026
Vulnerability identifier: #VU154293
CSH Severity: Low
CVSS v4: 5.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N]
CVE-ID: CVE-2026-102859
CWE-ID: CWE-79
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to perform spoofing.
The vulnerability exists due to improper neutralization of input in the web page generation functionality of Microsoft SharePoint Server when generating web pages. A remote user can exploit cross-site scripting over the network to perform spoofing.
Exploitation requires user interaction. The Preview Pane is not an attack vector.
Affected software
Microsoft SharePoint Server
How to mitigate CVE-2026-102859
Install security update from vendor's website.
Microsoft SharePoint Server - update to 16.0.20326.20190