Medium severity · published Jun 8, 2021
CVE-2021-31978
Microsoft Defender Denial of Service Vulnerability
5.5
CVSS
1.2%
EPSS
No
On KEV
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.2% · higher than 69% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MP
Malware Protection Engine · Microsoft
before 1.1.18200.3 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-31978
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-31978
Patch
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31978
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