MicrosoftCVE-2026-50349
Microsoft Windows Ancillary Function Driver for WinSock: race condition
High7.0CVE-2026-50349 · Published Sep 8, 2026 · updated Sep 24, 2026
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.
Affected versions
| Package | Affected | Fixed in |
|---|---|---|
| Windows 10 Version 1607 Product | >= 10.0.14393.0, < 10.0.14393.9512 | 10.0.14393.9512 |
| Windows 10 Version 1809 Product | >= 10.0.17763.0, < 10.0.17763.9245 | 10.0.17763.9245 |
| Windows 10 Version 21H2 Product | >= 10.0.19044.0, < 10.0.19044.7725 | 10.0.19044.7725 |
| Windows 10 Version 22H2 Product | >= 10.0.19045.0, < 10.0.19045.7725 | 10.0.19045.7725 |
| Windows 11 Version 23H2 Product | >= 10.0.22631.0, < 10.0.22631.7582 | 10.0.22631.7582 |
| Windows 11 Version 24H2 Product | >= 10.0.26100.0, < 10.0.26100.9445 | 10.0.26100.9445 |
| Windows 11 Version 25H2 Product | >= 10.0.26200.0, < 10.0.26200.9445 | 10.0.26200.9445 |
| Windows 11 version 23H2 Product | >= 10.0.22631.0, < 10.0.22631.7582 | 10.0.22631.7582 |
| Windows 11 version 26H1 Product | >= 10.0.28000.0, < 10.0.28000.2954 | 10.0.28000.2954 |
| Windows Server 2012 Product | >= 6.2.9200.0, < 6.2.9200.26349 | 6.2.9200.26349 |
| Windows Server 2012 (Server Core installation) Product | >= 6.2.9200.0, < 6.2.9200.26349 | 6.2.9200.26349 |
| Windows Server 2012 R2 Product | >= 6.3.9600.0, < 6.3.9600.23398 | 6.3.9600.23398 |
Details and references
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