CVE-2026-34344
Windows Ancillary Function Driver for WinSock Elevation of Privilege vulnerability
MSRC advisory May 12, 2026
Alert details
- Source feed
- Microsoft MSRC
- CVE ID
- CVE-2026-34344
- Affected products
- Windows Ancillary Function Driver for WinSock Elevation of Privilege · Microsoft Windows Ancillary Function Driver for WinSock Elevation of Privilege · Microsoft
What happened
Access of resource using incompatible type ('type confusion') in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.
What it means for your business
Windows Ancillary Function Driver for WinSock Elevation of Privilege vulnerability (CVE-2026-34344) was added to Microsoft’s security update guidance. Access of resource using incompatible type ('type confusion') in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally. PremierePC tracks MSRC advisories for Upstate SC businesses — patch or open a ticket if you need help verifying exposure.
EPSS probability
0.31%
Sources
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Need help patching?
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