Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability
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describes (1)
Related CVEs.
| ID | severity | exploitable | ||
|---|---|---|---|---|
| CVE-2026-21241US | — | — | ||
Use after free in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally. | ||||
references
External citations — patches, advisories, analysis.
- CVE-2026-21241 Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability - CSAFself
- CVE-2026-21241 Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability - HTMLself
- Microsoft Support Lifecycleexternal
- Common Vulnerability Scoring Systemexternal
- Microsoft Exploitability Indexexternal
remediations (13)
- FixedWindows 11 Version 23H2 for ARM64-based Systems
10.0.22631.6649:Security Update:https://support.microsoft.com/help/5075941
https://support.microsoft.com/help/5075941 - FixedWindows 11 Version 23H2 for x64-based Systems
10.0.22631.6649:Security Update:https://support.microsoft.com/help/5075941
https://support.microsoft.com/help/5075941 - FixedWindows 11 Version 24H2 for ARM64-based Systems
10.0.26100.7840:Security Update:https://support.microsoft.com/help/5077181
https://support.microsoft.com/help/5077181 - FixedWindows 11 Version 24H2 for x64-based Systems
10.0.26100.7840:Security Update:https://support.microsoft.com/help/5077181
https://support.microsoft.com/help/5077181 - FixedWindows 11 Version 25H2 for ARM64-based Systems
10.0.26200.7840:Security Update:https://support.microsoft.com/help/5077181
https://support.microsoft.com/help/5077181 - FixedWindows 11 Version 25H2 for x64-based Systems
10.0.26200.7840:Security Update:https://support.microsoft.com/help/5077181
https://support.microsoft.com/help/5077181 - FixedWindows 11 Version 26H1 for ARM64-based Systems
10.0.28000.1575:Security Update:https://support.microsoft.com/help/5077179
https://support.microsoft.com/help/5077179 - FixedWindows 11 version 26H1 for x64-based Systems
10.0.28000.1575:Security Update:https://support.microsoft.com/help/5077179
https://support.microsoft.com/help/5077179 - FixedWindows Server 2022
10.0.20348.4773:Security Update:https://support.microsoft.com/help/5075906
https://support.microsoft.com/help/5075906 - FixedWindows Server 2022 (Server Core installation)
10.0.20348.4773:Security Update:https://support.microsoft.com/help/5075906
https://support.microsoft.com/help/5075906 - FixedWindows Server 2022, 23H2 Edition (Server Core installation)
10.0.25398.2149:Security Update:https://support.microsoft.com/help/5075897
https://support.microsoft.com/help/5075897 - FixedWindows Server 2025
10.0.26100.32370:Security Update:https://support.microsoft.com/help/5075899
https://support.microsoft.com/help/5075899 - FixedWindows Server 2025 (Server Core installation)
10.0.26100.32370:Security Update:https://support.microsoft.com/help/5075899
https://support.microsoft.com/help/5075899
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