CVE-2021-26867 json
Windows Hyper-V Remote Code Execution Vulnerability
published 2021-03-11 5 y ago modified 2026-08-19 2 mo ago also EUVD-2021-13651
- cvss
- 9.9
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 2.9%
- EPSS 2.9% chance of exploitation in 30 days, percentile 86%
- public exploits
- 0
- none known
Summary
Windows Hyper-V Remote Code Execution Vulnerability
Patch / fix
- Microsoft Windows 10 Version 1909 10.0.18363.1440
- Microsoft Windows 10 Version 2004 10.0.19043.867
- Microsoft Windows Server version 2004 10.0.19043.867
- Microsoft Windows Server version 20H2 10.0.19043.867
- Microsoft Windows Server, version 1909 (Server Core installation) 10.0.18363.1440
Exploit prediction
2.87% chance of exploitation in the next 30 days, higher than 86% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 9.9 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C |
| CNA | 3.1 | 9.9 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H |
| CNA | 3.1 | 8.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H |
| NVD | 2.0 | 7.2 | AV:L/AC:L/Au:N/C:C/I:C/A:C |
Affected products
- Microsoft Windows 10 Version 1909
- Microsoft Windows 10 Version 2004
- Microsoft Windows Server version 2004
- Microsoft Windows Server version 20H2
- Microsoft Windows Server, version 1909 (Server Core installation)
References
-
msrc.microsoft.com
/update-guide/vulnerability/CVE-2021-26867
vendor-advisory, patch
-
portal.msrc.microsoft.com
/en-US/security-guidance/advisory/CVE-2021-26867
patch, vendor-advisory
Sources
- CVE List CVE-2021-26867
- NVD CVE-2021-26867
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