CVE-2026-71338: CWE-415: Double Free in Microsoft Windows 10 Version 1607
Description
CVE-2026-71338 is a double free vulnerability in the Windows Failover Cluster component affecting multiple versions of Microsoft Windows 10, including Version 1607. This flaw allows an authorized local attacker with high privileges to elevate their privileges further. The vulnerability has a CVSS score of 6.4 (medium severity) and has been officially fixed by Microsoft.
CVSS v3.1
Score 6.4medium
Affected software
Microsoft
Windows 10 Version 1607
Microsoft
Windows 10 Version 1809
Microsoft
Windows Server 2012
Microsoft
Windows Server 2012 (Server Core installation)
Microsoft
Windows Server 2012 R2
Microsoft
Windows Server 2012 R2 (Server Core installation)
Microsoft
Windows Server 2016
Microsoft
Windows Server 2016 (Server Core installation)
Microsoft
Windows Server 2019
Microsoft
Windows Server 2019 (Server Core installation)
Microsoft
Windows Server 2022
Microsoft
Windows Server 2025
Microsoft
Windows Server 2025 (Server Core installation)
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability is a double free condition in the Windows Failover Cluster component that can be exploited by an authorized attacker with local access and high privileges to elevate their privileges. The affected versions include several builds of Windows 10 and Windows Server versions prior to specific patch levels. Microsoft has released an official fix for this vulnerability. The CVSS 3.1 vector indicates that the attack requires local access, high complexity, and high privileges, but no user interaction. The impact includes high confidentiality, integrity, and availability impacts.
Potential Impact
An authorized local attacker with high privileges can exploit this double free vulnerability to elevate their privileges further on the affected Windows systems. This could lead to complete compromise of the affected system's confidentiality, integrity, and availability.
Mitigation Recommendations
Microsoft has released an official fix for this vulnerability. Users and administrators should apply the security updates provided by Microsoft to the affected Windows versions as soon as possible to remediate this issue.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-08-05T18:41:50.334Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-71338","vendor":"Microsoft"}]
Threat ID: 6aa04540acd9273b49fa9c39
Added to database: 09/08/2026, 17:26:24 UTC
Last enriched: 10/16/2026, 21:43:14 UTC
Last updated: 10/23/2026, 15:10:14 UTC
Views: 22
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