Windows
CVE-2026-20809
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 Kernel Memory allows an authorized attacker to elevate privileges locally.
AnalysisAI
Privilege escalation in Windows Kernel Memory affects Windows 10 21h2 and Windows Server 2022 23h2, exploitable by local authenticated users through a race condition between permission checks and memory access. An attacker with local access can leverage this window to gain elevated system privileges. No patch is currently available.
Technical ContextAI
Classified as CWE-122 (Heap-based Buffer Overflow). Affects Windows 10 1607. Time-of-check time-of-use (toctou) race condition in Windows Kernel Memory allows an authorized attacker to elevate privileges locally.
RemediationAI
Monitor vendor advisories for a patch.
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Same weakness CWE-122 – Heap-based Buffer Overflow
View allSame technique Race Condition
View allShare
External POC / Exploit Code
Leaving vuln.today