CVE-2026-56164: Microsoft SharePoint Server

What is CVE-2026-56164?

Missing authentication for critical function in Microsoft Office SharePoint allows an unauthorized attacker to elevate privileges over a network.

CVSS9.8 NVD 3.1

SeverityCRITICAL

Exploitation In the wild In CISA KEV

Triage statusActive Exploit

ActionPatch immediately

CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CWECWE-306

NVD published2026-07-14

NVD last modified2026-07-14

Timeline

2026-07-14Published to the U.S. National Vulnerability Database (NVD)
2026-07-14Added to the CISA Known Exploited Vulnerabilities (KEV) catalog
2026-07-17CISA federal remediation deadline (BOD 22-01)

CISA Known Exploited Vulnerability

Microsoft SharePoint Server Missing Authentication for Critical Function Vulnerability

Added to KEV2026-07-14

Federal patch deadline2026-07-17

Known ransomware useUnknown

Affected product

Microsoft SharePoint Server

Remediation Steps

Apply Microsoft July 2026 Patch Tuesday updates for SharePoint immediately
Review SharePoint access logs for signs of active exploitation
Harden SharePoint instances per CISA guidance
Restrict remote access to SharePoint administration interfaces

References

Referenced in our briefings & reports

Vulnerability Priority Report – Week 2 of July 2026 (July 13 – 19)

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🤖 This CVE page is generated by defend.network from NVD, CISA KEV, EPSS, and our verified daily briefings. Severity and exploitation data come from official sources; always verify remediation steps against the official vendor advisory before acting in production.