Windows
CVE-2026-20831
HIGH
Severity by source
AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Lifecycle Timeline
2DescriptionCVE.org
Time-of-check time-of-use (toctou) race condition in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.
AnalysisAI
Windows Ancillary Function Driver for WinSock contains a race condition that enables local privilege escalation on affected Windows systems including Server 2008, Server 2019, and Windows 10 22H2. An authenticated attacker can exploit this timing vulnerability to gain elevated privileges with high impact to confidentiality, integrity, and availability. No patch is currently available for this vulnerability.
Technical ContextAI
Affects the Windows Ancillary component of Windows 10 1607. Time-of-check time-of-use (toctou) race condition in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.
RemediationAI
Monitor vendor advisories for a patch.
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External POC / Exploit Code
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