CVE-2021-1647
ENISA EUVD: EUVD-2021-7114 ↗
Exploited in the Wild
✓ Confirmed 0-Day
★ Google Project Zero
Triaged: March 3, 2026
3 articles
EPSS Score
Source: FIRST.org · 2026-05-24
77.39%
probability
This CVE has a 77.39% probability
of being exploited in the next 30 days.
0%
Top 99.0th percentile of all CVEs
100%
CVSS v3.1
Source: NVD7.8
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
Temporal
Exploit Code Maturity
Proof-of-Concept
Remediation Level
Official Fix
Report Confidence
Confirmed
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
Description
Project ZeroUnspecified remote code execution in Windows Defender
Affected Products
Google Project Zero
Patched
Jan. 12, 2021
Reported by
???
Root Cause Analysis
https://googleprojectzero.github.io/0days-in-the-wild/0day-RCAs/2021/CVE-2021-1647.html
Security Advisory 2021-001
CERT-EU
Jan 13, 2021
January 2021 Patch Tuesday – 83 Vulnerabilities, 10 Critical, One Zero Day, Adobe
Qualys
Jan 12, 2021
Qualys Response to CISA Alert: Binding Operational Directive 22-01
Qualys
Nov 09, 2021
Signal Intelligence
Confidence
82%
EPSS
77.39%
CVSS v3.1
7.8
Mentions
3
Last Seen
Nov 09, 2021
CNA Information
Analyst Note
This CVE is confirmed as a legitimate remote code execution vulnerability in Microsoft Defender with a high CVSS score (7.8). While it lacks CISA KEV listing, the inclusion in Google Project Zero and an official CERT-EU security advisory (with high signal score) provide strong corroboration of its authenticity and severity.
Triage Info
Decided atMar 03, 2026