CVE-2026-64921 - Vulnerability Details - OpenCVE

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

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Exploitation none

Automatable no

Technical Impact total

Vendors	Products
Microsoft	Sharepoint Server Sharepoint Server 2016 Sharepoint Server 2019

No data.

No data.

No data.

References

Link	Providers
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-64921

History

Tue, 11 Aug 2026 19:30:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}`

Tue, 11 Aug 2026 17:15:00 +0000

Type	Values Removed	Values Added
Description		Missing authentication for critical function in Microsoft Office SharePoint allows an authorized attacker to elevate privileges over a network.
Title		Microsoft SharePoint Server Elevation of Privilege Vulnerability
First Time appeared		Microsoft Microsoft sharepoint Server Microsoft sharepoint Server 2016 Microsoft sharepoint Server 2019
Weaknesses		CWE-306
CPEs		cpe:2.3:a:microsoft:sharepoint_server:::::subscription:::* cpe:2.3:a:microsoft:sharepoint_server_2016:::::enterprise:::* cpe:2.3:a:microsoft:sharepoint_server_2019::::::::
Vendors & Products		Microsoft Microsoft sharepoint Server Microsoft sharepoint Server 2016 Microsoft sharepoint Server 2019
References		https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-64921
Metrics		cvssV3_1 `{'score': 8.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C'}`

MITRE

Status: PUBLISHED

Assigner: microsoft

Published: 2026-08-11T17:06:46.993Z

Updated: 2026-08-11T19:19:55.246Z

Reserved: 2026-07-20T20:25:40.977Z

Link: CVE-2026-64921

Vulnrichment

Updated: 2026-08-11T18:27:01.756Z

NVD

Status : Undergoing Analysis

Published: 2026-08-11T17:18:53.463

Modified: 2026-08-11T19:18:30.007

Link: CVE-2026-64921

Redhat

No data.

OpenCVE Enrichment

No data.

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