CVE-2021-31977 json
Windows Hyper-V Denial of Service Vulnerability
published 2021-06-08 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-18849
- cvss
- 8.6
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 3.2%
- EPSS 3.2% chance of exploitation in 30 days, percentile 88%
- public exploits
- 0
- none known
Summary
Windows Hyper-V Denial of Service Vulnerability
Patch / fix
- Microsoft Windows 10 Version 1809 10.0.17763.1999
- Microsoft Windows Server 2019 10.0.17763.1999
- Microsoft Windows Server 2019 (Server Core installation) 10.0.17763.1999
- Microsoft Windows 10 Version 1909 10.0.18363.1621
- Microsoft Windows 10 Version 21H1 10.0.19043.1052
- Microsoft Windows 10 Version 2004 10.0.19041.1052
- Microsoft Windows Server version 2004 10.0.19041.1052
- Microsoft Windows Server version 20H2 10.0.19042.1052
- Microsoft Windows 10 Version 1507 10.0.10240.18967
- Microsoft Windows 10 Version 1607 10.0.14393.4467
- Microsoft Windows Server 2016 10.0.14393.4467
- Microsoft Windows Server 2016 (Server Core installation) 10.0.14393.4467
Exploit prediction
3.18% chance of exploitation in the next 30 days, higher than 88% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 8.6 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H/E:U/RL:O/RC:C |
| CNA | 3.1 | 8.6 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H |
| NVD | 2.0 | 5.0 | AV:N/AC:L/Au:N/C:N/I:N/A:P |
Affected products
- Microsoft Windows 10 Version 1809
- Microsoft Windows Server 2019
- Microsoft Windows Server 2019 (Server Core installation)
- Microsoft Windows 10 Version 1909
- Microsoft Windows 10 Version 21H1
- Microsoft Windows 10 Version 2004
- Microsoft Windows Server version 2004
- Microsoft Windows Server version 20H2
- Microsoft Windows 10 Version 1507
- Microsoft Windows 10 Version 1607
- Microsoft Windows Server 2016
- Microsoft Windows Server 2016 (Server Core installation)
Classification
- Weakness
-
- CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer
References
-
portal.msrc.microsoft.com
/en-US/security-guidance/advisory/CVE-2021-31977
patch, vendor-advisory
Sources
- CVE List CVE-2021-31977
- NVD CVE-2021-31977
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.