CVE-2021-31978 json
Microsoft Defender Denial of Service Vulnerability
published 5y ago modified 4mo ago also EUVD-2021-18850
- cvss
- 5.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.2%
- EPSS 1.2% chance of exploitation in 30 days, percentile 69%
- public exploits
- 0
- none known
Summary
Microsoft Defender Denial of Service Vulnerability
Patch / fix
- Microsoft Microsoft Malware Protection Engine Version 1.1.18200.3
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1.23% chance of exploitation in the next 30 days, higher than 69% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 5.5 | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C |
| CNA | 3.1 | 5.5 | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H |
| CNA | 3.1 | 5.5 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
| NVD | 2.0 | 2.1 | AV:L/AC:L/Au:N/C:N/I:N/A:P |
Affected products
- Microsoft Microsoft Malware Protection Engine
References
-
portal.msrc.microsoft.com
/en-US/security-guidance/advisory/CVE-2021-31978
patch, vendor-advisory
Sources
- CVE List CVE-2021-31978
- NVD CVE-2021-31978
Fencer Intel 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.