CVE-2026-64921: CWE-306: Missing Authentication for Critical Function in Microsoft Microsoft SharePoint Enterprise Server 2016
Missing authentication for critical function in Microsoft Office SharePoint allows an authorized attacker to elevate privileges over a network.
AI Analysis
Technical Summary
This vulnerability (CWE-306) in Microsoft SharePoint Enterprise Server 2016 version 16.0.0 is caused by missing authentication controls on a critical function, enabling an attacker with some level of authorization to escalate privileges remotely. The CVSS v3.1 base score is 8.8, reflecting high impact on confidentiality, integrity, and availability. Microsoft has published an official fix for this vulnerability, as detailed in their security update guide.
Potential Impact
An authorized attacker can exploit this vulnerability over a network to gain elevated privileges, potentially leading to full compromise of the affected SharePoint server's confidentiality, integrity, and availability. This could allow unauthorized access to sensitive information and administrative functions.
Mitigation Recommendations
Apply the official security update provided by Microsoft for SharePoint Enterprise Server 2016 version 16.0.0 as soon as possible. The vendor advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-64921 contains the authoritative remediation instructions.
CVE-2026-64921: CWE-306: Missing Authentication for Critical Function in Microsoft Microsoft SharePoint Enterprise Server 2016
Description
Missing authentication for critical function in Microsoft Office SharePoint allows an authorized attacker to elevate privileges over a network.
CVSS v3.1
Score 8.8high
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CWE-306) in Microsoft SharePoint Enterprise Server 2016 version 16.0.0 is caused by missing authentication controls on a critical function, enabling an attacker with some level of authorization to escalate privileges remotely. The CVSS v3.1 base score is 8.8, reflecting high impact on confidentiality, integrity, and availability. Microsoft has published an official fix for this vulnerability, as detailed in their security update guide.
Potential Impact
An authorized attacker can exploit this vulnerability over a network to gain elevated privileges, potentially leading to full compromise of the affected SharePoint server's confidentiality, integrity, and availability. This could allow unauthorized access to sensitive information and administrative functions.
Mitigation Recommendations
Apply the official security update provided by Microsoft for SharePoint Enterprise Server 2016 version 16.0.0 as soon as possible. The vendor advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-64921 contains the authoritative remediation instructions.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-07-20T20:25:40.977Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-64921","vendor":"Microsoft"}]
Threat ID: 6a7b582bbf8831d53915633c
Added to database: 08/11/2026, 17:13:15 UTC
Last enriched: 08/11/2026, 20:13:33 UTC
Last updated: 08/12/2026, 00:21:20 UTC
Views: 3
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