CVE-2026-70342: Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability
Use after free in Windows Ancillary Function Driver for WinSock allows an unauthorized attacker to elevate privileges over a network.
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 6.2.9200.26349Patch KB5123065 - Upgrade
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Fixed in 6.3.9600.23397Patch KB5123066 - Upgrade
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Fixed in 10.0.14393.9512Patch KB5123099 - Upgrade
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Fixed in 10.0.28000.2954Patch KB5124012 - Upgrade
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Fixed in 10.0.26100.33438Patch KB5122871 - Upgrade
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Fixed in 10.0.19045.7725Patch KB5122878 - Upgrade
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Fixed in 10.0.26100.9445Patch KB5124008 - Upgrade
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Fixed in 10.0.22631.7582Patch KB5122880 - Upgrade
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Fixed in 10.0.26200.9445Patch KB5124008 - Upgrade
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Fixed in 10.0.19044.7725Patch KB5122878 - Upgrade
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Fixed in 10.0.20348.5622Patch KB5122882 - Upgrade
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Fixed in 10.0.17763.9245Patch KB5122876
Event History
Frequently Asked Questions
Which systems are identified as affected?
The listed affected products are Microsoft Windows 10, Windows 11, Windows Server 2012, Windows Server 2012 R2, Windows Server 2016, Windows Server 2019, Windows Server 2022, and Windows Server 2025.
Can this be exploited remotely without credentials or user interaction?
The vector is network-based, and the metrics indicate no privileges or user interaction are required. Exploitation complexity is rated high, meaning successful exploitation requires conditions beyond simply reaching a vulnerable system over the network.
What impact could successful exploitation have?
Successful exploitation allows an unauthorized attacker to elevate privileges. The supplied impact metrics rate confidentiality, integrity, and availability impact as high.