CVE-2026-70306: Microsoft SharePoint Server

Critical severity, CVSS 9.3. EPSS: 1% chance of exploitation in the next 30 days.

Improper neutralization of input during web page generation ('cross-site scripting') in Microsoft Office SharePoint allows an unauthorized attacker to perform spoofing over a network.

Affected products

• Microsoft SharePoint Server: before 16.0.19725.20434 (fixed in 16.0.19725.20434); version 2016 only; version 2019 only

Published 2026-08-11. Last modified 2026-08-16.