Main Vulnerability Database Vulnerabilities #VU141484

Missing Authentication for Critical Function in Microsoft products - CVE-2026-64921

Published: August 11, 2026

Vulnerability identifier: #VU141484

CSH Severity: Medium

CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-64921

CWE-ID: CWE-306

Exploitation vector: Remote access

Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a remote attacker to bypass implemented security restrictions.

The vulnerability exists due to Missing authentication for critical function in Microsoft SharePoint Server. A remote user can gain elevated privileges on the target system.

Affected software

Microsoft SharePoint Enterprise Server
Microsoft SharePoint Server
Microsoft SharePoint Server Subscription Edition

How to mitigate CVE-2026-64921

Install updates from vendor's website.

Microsoft SharePoint Enterprise Server - update to 16.0.5565.1001
Microsoft SharePoint Server - update to 16.0.10417.20198
Microsoft SharePoint Server Subscription Edition - update to 16.0.19725.20522

External References

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

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