Description
Use after free in Windows Hyper-V allows an unauthorized attacker to elevate privileges locally.
Affected products
microsoft: windows 11 23h2; microsoft: windows server 2022
References1
- msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40402 Vendor Advisory
Metrics
- CVSS 3.1
-
9.3
CRITICAL
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 27 · as of 14 November 2026
- CWE
- CWE-416
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.