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Vulnerability record · CVE-2021-42298 · published 10 November 2021
CVE-2021-42298: Microsoft malware protection engine code injection vulnerability
Microsoft · Malware Protection Engine
Microsoft Defender Remote Code Execution Vulnerability
7.8 CVSS 3.1 High EPSS 5.8% · top 7.1% CWE-94 · Code injection
7.8CVSS 3.1 base score, v2 9.3
5.8%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
2References
19 Aug 2026Last modified by NVD
Description
Microsoft Defender Remote Code Execution Vulnerability
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Affected products
1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.
References
| Link | Tags |
|---|---|
| https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-42298 | |
| https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-42298 | MitigationPatchVendor Advisory |
Track CVE-2021-42298 inside VULONE
Watch it alongside the ransomware crews, C2 infrastructure and forum chatter that reference it, query it through the API and pull it into your SIEM over TAXII.
Related vulnerabilities
Same products first, then exploited flaws of the same weakness class.
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Source: NIST National Vulnerability Database (record CVE-2021-42298), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.
