by Kastro
Paper/Archive/CVE-2026-40402

CVE-2026-40402

Microsoft Windows 11 version 23H2 — Windows Hyper-V Elevation of Privilege Vulnerability

EPSS 0.3%CVSS 9.3
critical.is priorityof 100
33
CVSS 9.3 (CNA)9.3 / 10 × 3027.9Not in CISA KEV+300.0EPSS percentile 26.5.265 × 205.3No public exploit+100.0SSVC exploitation: none+100.0
Description · from the CVE record

Use after free in Windows Hyper-V allows an unauthorized attacker to elevate privileges locally.

Affected

ProductAffectedFixed inSource
Windows 11 version 23H210.0.22631.0 – < 10.0.22631.707910.0.22631.7079CNA
Windows 11 Version 23H210.0.22631.0 – < 10.0.22631.721910.0.22631.7219CNA
Windows Server 202210.0.20348.0 – < 10.0.20348.513910.0.20348.5139CNA

Scores by source

microsoft (CNA)9.3CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C
CISA ADPSSVCExploitation: none · Automatable: no · Technical impact: total

References

patchmsrc.microsoft.com/update-guide/vulnerability/CVE-2026-40402