CVE-2021-34522: Microsoft Malware Protection Engine

High severity, CVSS 7.8. EPSS: 2.7% chance of exploitation in the next 30 days.

Microsoft Defender Remote Code Execution Vulnerability

Affected products

• Microsoft Malware Protection Engine: before 1.1.18242.0 (fixed in 1.1.18242.0)

Published 2021-07-14. Last modified 2026-08-10.