CVE-2026-45601: Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability
Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.
Other sources
Use after free in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.
— Microsoft
Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability
— Microsoft
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 6.2.9200.26132Patch KB5094042 - 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 10.0.26100.32995Patch KB5094125 - Upgrade
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Fixed in 10.0.28000.2269Patch KB5095051 - Upgrade
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Fixed in 10.0.22631.7219Patch KB5093998 - Upgrade
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Fixed in 10.0.26100.8655Patch KB5094126 - Upgrade
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Fixed in 10.0.26200.8655Patch KB5094126 - 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 10.0.20348.5256Patch KB5094128 - Upgrade
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Fixed in 10.0.17763.8880Patch KB5094123
Event History
Frequently Asked Questions
What is the severity of CVE-2026-45601?
The severity of CVE-2026-45601 is rated as high with a score of 7.
What can an attacker achieve by exploiting CVE-2026-45601?
An attacker can elevate privileges locally on affected Microsoft Windows systems.
Which versions of Windows are affected by CVE-2026-45601?
CVE-2026-45601 affects Microsoft Windows 10, Windows 11, and various Windows Server versions including 2012, 2016, 2019, 2022, and 2025.
How do I fix CVE-2026-45601?
To fix CVE-2026-45601, apply the latest security updates provided by Microsoft for your specific Windows version.
What type of vulnerability is CVE-2026-45601 classified as?
CVE-2026-45601 is classified as a use after free vulnerability that can lead to elevation of privilege.