XSS in Microsoft Sharepoint Enterprise Server 2016
CVE-2026-20959
Improper neutralization of input during web page generation ('cross-site scripting') in Microsoft Office SharePoint allows an authorized attacker to perform spoofing over a network.
Vulnerability class: XSS (Cross-Site Scripting)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 4.6 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N.
EPSS exploit prediction
EPSS: 0.076 (94.3th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 94th percentile — 94.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.072 · newest: 0.076 · change: +0.003
Affected products
- Microsoft Sharepoint Enterprise Server 2016 — versions 16.0.0
- Microsoft Sharepoint Server 2019 — versions 16.0.0
- Microsoft Sharepoint Server Subscription Edition — versions 16.0.0
- Microsoft Sharepoint Server — versions 2016, 2019
Weakness classification (CWE)
References
- Microsoft SharePoint Server Spoofing Vulnerability (vendor-advisory, patch, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-20959?
- CVE-2026-20959 is a medium-severity vulnerability in Microsoft Sharepoint Enterprise Server 2016, classified under Cross-site Scripting. CVSS score: 4.6/10. Published 2026-01-13.
- How severe is CVE-2026-20959?
- Medium severity. CVSS v3 base score is 4.6 out of 10.