CVE-2026-40402 json
Windows Hyper-V Elevation of Privilege Vulnerability
published 2026-05-12 5 mo ago modified 2026-08-10 2 mo ago also EUVD-2026-29663
- cvss
- 9.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 26%
- public exploits
- 0
- none known
Summary
Use after free in Windows Hyper-V allows an unauthorized attacker to elevate privileges locally.
Patch / fix
- Microsoft Windows 11 version 23H2 10.0.22631.7079, 10.0.22631.7219
- Microsoft Windows Server 2022 10.0.20348.5139
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 5 mo ago
Exploit prediction
0.33% chance of exploitation in the next 30 days, higher than 26% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 9.3 | CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C |
| CNA | 3.1 | 9.3 | CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H |
Affected products
- Microsoft Windows 11 version 23H2
- Microsoft Windows Server 2022
Classification
- Weakness
-
- CWE-416 Use After Free
References
-
msrc.microsoft.com
/update-guide/vulnerability/CVE-2026-40402
vendor-advisory, patch
Sources
- CVE List CVE-2026-40402
- NVD CVE-2026-40402
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