CVE-2021-31978
lowpriority · track · 8EPSS 0.012 · 69 %ileEURUUSgrimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
1.23% (69th) EPSS
CVSS 2.1 · low
Who says so?
4 sources
cnnvd · enisa_euvd · fstec_bdu · nvd
EPSS · scored 2026-10-27
Microsoft Defender Denial of Service Vulnerability
01
cvss
Technical severity, 0–10. One row per scoring source.
5.5
010
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–medium · 1.8–5.5
v3.15.5mediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Hsecondary · NVD / NIST USexploitability 1.8 · impact 3.6
v3.15.5mediumCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:Hsecondary · secure@microsoft.com USexploitability 1.8 · impact 3.6
02
weaknesses
The CWE weakness classes this flaw belongs to.
03
affected products (3)
Products and version ranges known to be affected.
- microsoft malware protection engine< 1.1.18200.3nvdUScpe:2.3:a:microsoft:malware_protection_engine:*:*:*:*:*:*:*:*
04
also known as (4)
Other names and identifiers for this entity.
05
sources
Which sources assert this record, and when.
06
references (5)
External citations — patches, advisories, analysis.
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-31978cnnvd
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31978cnnvd
- https://www.cybersecurity-help.cz/vdb/SB2021060834cnnvd
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31978enisa_euvd
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31978PatchVendor Advisorynvd
scry
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