CVE-2026-42911: Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability
Use after free in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.
Other sources
Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability
— Microsoft
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
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Fixed in 10.0.17763.8880Patch KB5094123 - Upgrade
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Fixed in 6.3.9600.23228Patch KB5094041 - Upgrade
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Fixed in 10.0.14393.9234Patch KB5094122 - Upgrade
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Fixed in 10.0.19045.7417Patch KB5094127 - Upgrade
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Fixed in 10.0.19044.7417Patch KB5094127 - Upgrade
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Fixed in 6.2.9200.26132Patch KB5094042 - Upgrade
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Fixed in 10.0.20348.5256Patch KB5094128 - Upgrade
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Fixed in 10.0.28000.2269Patch KB5095051 - Upgrade
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Fixed in 10.0.26100.32995Patch KB5094125 - Upgrade
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Fixed in 10.0.26100.8655Patch KB5094126 - Upgrade
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Fixed in 10.0.22631.7219Patch KB5093998 - Upgrade
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Fixed in 10.0.26200.8655Patch KB5094126
Event History
Frequently Asked Questions
What is the severity of CVE-2026-42911?
The severity of CVE-2026-42911 is assessed as high with a score of 7.
How do I fix CVE-2026-42911?
To fix CVE-2026-42911, apply the latest security updates provided by Microsoft for affected Windows versions.
What are the affected systems for CVE-2026-42911?
CVE-2026-42911 affects Microsoft Windows 10, Windows 11, and multiple versions of Windows Server including 2012, 2016, 2019, 2022, and 2025.
What type of vulnerability is CVE-2026-42911?
CVE-2026-42911 is classified as a 'Use After Free' vulnerability.
What impacts can CVE-2026-42911 have?
CVE-2026-42911 allows an authorized attacker to elevate privileges locally on affected systems.