CVE-2026-42911: CWE-416: Use After Free in Microsoft Windows 10 Version 1607
CVE-2026-42911 is a use-after-free vulnerability in the Windows Ancillary Function Driver for WinSock on Windows 10 Version 1607. This flaw allows an authorized local attacker to elevate privileges. The vulnerability has a high severity rating and a CVSS score of 7. An official fix is available from Microsoft.
AI Analysis
Technical Summary
This vulnerability involves a use-after-free condition in the Windows Ancillary Function Driver for WinSock on Windows 10 Version 1607 (build 10.0.14393.0). Exploitation requires local access with low privileges but no user interaction. Successful exploitation can lead to elevation of privileges, impacting confidentiality, integrity, and availability. Microsoft has published an official fix to address this issue.
Potential Impact
An authorized local attacker can exploit this use-after-free vulnerability to elevate privileges on the affected system. This could allow the attacker to gain higher-level access than intended, potentially leading to full system compromise. The CVSS score of 7 indicates a high impact on confidentiality, integrity, and availability.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the security update provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-42911 to remediate this vulnerability.
CVE-2026-42911: CWE-416: Use After Free in Microsoft Windows 10 Version 1607
Description
CVE-2026-42911 is a use-after-free vulnerability in the Windows Ancillary Function Driver for WinSock on Windows 10 Version 1607. This flaw allows an authorized local attacker to elevate privileges. The vulnerability has a high severity rating and a CVSS score of 7. An official fix is available from Microsoft.
CVSS v3.1
Score 7.0high
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves a use-after-free condition in the Windows Ancillary Function Driver for WinSock on Windows 10 Version 1607 (build 10.0.14393.0). Exploitation requires local access with low privileges but no user interaction. Successful exploitation can lead to elevation of privileges, impacting confidentiality, integrity, and availability. Microsoft has published an official fix to address this issue.
Potential Impact
An authorized local attacker can exploit this use-after-free vulnerability to elevate privileges on the affected system. This could allow the attacker to gain higher-level access than intended, potentially leading to full system compromise. The CVSS score of 7 indicates a high impact on confidentiality, integrity, and availability.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the security update provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-42911 to remediate this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-04-30T22:35:54.968Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-42911","vendor":"Microsoft"}]
Threat ID: 6a284cc48dd33fbd85664811
Added to database: 6/9/2026, 5:26:28 PM
Last enriched: 6/9/2026, 11:11:15 PM
Last updated: 6/10/2026, 5:04:44 AM
Views: 2
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