5.3Medium KEV

CVE-2026-56164Microsoft SharePoint Server Elevation of Privilege Vulnerability

Microsoft Microsoft SharePoint Enterprise Server 2016; Microsoft Microsoft SharePoint Server 2019; Microsoft Microsoft SharePoint Server Subscription Edition Published: (3 months ago)

Known exploited — Microsoft SharePoint Server Missing Authentication for Critical Function Vulnerability

CISA confirmed this vulnerability is used in real attacks on 14.07.2026. Remediation deadline for US federal agencies: 17.07.2026.

Required action: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines. https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2026-56164 ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2026-56164

Description

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

Weakness (CWE): CWE-306

Data: CVE.org, NVD, CISA KEV, FIRST EPSS, Ubuntu. Published as the sources state it, in English.

Affected products and versions

VendorProductVersions
Microsoft Microsoft SharePoint Enterprise Server 2016 16.0.0 – < 16.0.5561.1001
Microsoft Microsoft SharePoint Server 2019 16.0.0 – < 16.0.10417.20175
Microsoft Microsoft SharePoint Server Subscription Edition 16.0.0 – < 16.0.19725.20434
microsoft sharepoint server 16.0.0 – < 16.0.19725.20434
microsoft sharepoint server 2016 16.0.0 – < 16.0.5561.1001
microsoft sharepoint server 2019 16.0.0 – < 16.0.10417.20175

References and patches

CPE matches (NVD) (3)

  • cpe:2.3:a:microsoft:sharepoint_server:*:*:*:*:subscription:*:*:* < 16.0.19725.20434
  • cpe:2.3:a:microsoft:sharepoint_server:2016:*:*:*:enterprise:*:*:*
  • cpe:2.3:a:microsoft:sharepoint_server:2019:*:*:*:*:*:*:*