CVE-2026-88149: CWE-415: Double Free in Microsoft Windows 10 Version 1607
Description
CVE-2026-88149 is a high severity vulnerability in Microsoft Windows 10 Version 1607 involving a double free flaw in the Windows Ancillary Function Driver for WinSock. This flaw allows an authorized local attacker to elevate privileges. The vulnerability affects multiple Windows 10 builds prior to specific patched versions. An official fix is available from Microsoft.
CVSS v3.1
Score 7.0high
Affected software
Microsoft
Windows 10 Version 1607
Microsoft
Windows 10 Version 1809
Microsoft
Windows 10 Version 21H2
Microsoft
Windows 10 Version 22H2
Microsoft
Windows 11 version 23H2
Microsoft
Windows 11 Version 23H2
Microsoft
Windows 11 Version 24H2
Microsoft
Windows 11 Version 25H2
Microsoft
Windows 11 version 26H1
Microsoft
Windows 11 Version 26H2
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 (CVE-2026-88149) is a double free condition in the Windows Ancillary Function Driver for WinSock on Microsoft Windows 10 Version 1607 and related builds. The flaw enables an authorized local attacker to elevate privileges on the affected system. The vulnerability has a CVSS 3.1 base score of 7.0, indicating high severity, with attack vector local, high attack complexity, low privileges required, no user interaction, and impacts confidentiality, integrity, and availability. Multiple Windows 10 versions are affected, with patches released by Microsoft to address the issue.
Potential Impact
An authorized local attacker can exploit this double free vulnerability to elevate privileges, potentially gaining higher system rights than intended. This could allow the attacker to execute code with elevated permissions, compromising system confidentiality, integrity, and availability.
Mitigation Recommendations
Microsoft has released official fixes for this vulnerability. Users and administrators should apply the security updates provided by Microsoft to affected Windows 10 versions as soon as possible. Since an official fix is available, remediation should be performed by installing these updates. No additional mitigation steps are indicated by the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-09-09T21:58:19.186Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-88149","vendor":"Microsoft"}]
Threat ID: 6ace85612cdf04f6569ff90d
Added to database: 10/13/2026, 19:24:17 UTC
Last enriched: 10/14/2026, 01:33:45 UTC
Last updated: 10/14/2026, 01:33:45 UTC
Views: 2
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