VulnerabilityModified
CVE-2021-31978
Microsoft Defender Denial of Service Vulnerability
MEDIUM 5.5EPSS 1.23%
Does this matter?
Lower severity and a low EPSS score (1.23%). Track it; it rarely justifies an emergency change on its own.
Description
Microsoft Defender Denial of Service Vulnerability
- CVSS 3.1
- 5.5 MEDIUMCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
- EPSS
- 1.23% probability · 69th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Affected
- microsoft/malware protection engine
- Source
- secure@microsoft.com
EPSS 1.2% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31978Patch, Vendor Advisory
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31978Patch, Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.