What is CVE-2026-20958?

CVE-2026-20958 is a medium-severity vulnerability in Microsoft Sharepoint Enterprise Server 2016, classified under Server-Side Request Forgery (SSRF). CVSS score: 5.4/10. Published 2026-01-13.

How severe is CVE-2026-20958?

Medium severity. CVSS v3 base score is 5.4 out of 10.

SSRF in Microsoft Sharepoint Enterprise Server 2016

CVE-2026-20958

Server-side request forgery (ssrf) in Microsoft Office SharePoint allows an authorized attacker to disclose information over a network.

Vulnerability class: SSRF (Server-Side Request Forgery)

EPSS: 0.003 (20.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N.

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-918 — Server-Side Request Forgery (SSRF)

References

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

Frequently asked questions

What is CVE-2026-20958?: CVE-2026-20958 is a medium-severity vulnerability in Microsoft Sharepoint Enterprise Server 2016, classified under Server-Side Request Forgery (SSRF). CVSS score: 5.4/10. Published 2026-01-13.
How severe is CVE-2026-20958?: Medium severity. CVSS v3 base score is 5.4 out of 10.