Vulnerability in Microsoft Security Essentials

CVE-2021-1647

Microsoft Defender Remote Code Execution Vulnerability

EPSS: 0.761 (98.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C.

Affected products

CISA KEV (Known Exploited Vulnerabilities)

This CVE is on the CISA KEV catalog, added on . CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.

BOD 22-01 due date: .

Required action: Apply updates per vendor instructions.

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2021-1647?
CVE-2021-1647 is a high-severity vulnerability in Microsoft Security Essentials. CVSS score: 7.8/10. Published 2021-01-12.
How severe is CVE-2021-1647?
High severity. CVSS v3 base score is 7.8 out of 10.
Is CVE-2021-1647 known to be exploited?
Yes. CVE-2021-1647 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2021-11-03), indicating it is being actively exploited. 20 public proof-of-concept repositories are indexed.