What is CVE-2026-20951?

CVE-2026-20951 is a high-severity vulnerability in Microsoft Sharepoint Enterprise Server 2016, classified under Improper Input Validation. CVSS score: 7.8/10. Published 2026-01-13.

How severe is CVE-2026-20951?

High severity. CVSS v3 base score is 7.8 out of 10.

Improper input validation in Microsoft Sharepoint Enterprise Server 2016

CVE-2026-20951

Improper input validation in Microsoft Office SharePoint allows an unauthorized attacker to execute code locally.

Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)

EPSS: 0.008 (51.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

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)

CWE-20 — Improper Input Validation

References

secure@microsoft.com (vendor-advisory, patch, Vendor Advisory)

Frequently asked questions

What is CVE-2026-20951?: CVE-2026-20951 is a high-severity vulnerability in Microsoft Sharepoint Enterprise Server 2016, classified under Improper Input Validation. CVSS score: 7.8/10. Published 2026-01-13.
How severe is CVE-2026-20951?: High severity. CVSS v3 base score is 7.8 out of 10.