Windows Defender AV must be configured to always enable real-time protection.

From MS Windows Defender Antivirus Security Technical Implementation Guide

Associated with: CCI-001242

SV-89907r2_rule Windows Defender AV must be configured to always enable real-time protection.

Vulnerability discussion

This policy setting turns off real-time protection prompts for known malware detection. Windows Defender Antivirus alerts you when malware or potentially unwanted software attempts to install itself or to run on your computer. If you enable this policy setting Windows Defender Antivirus will not prompt users to take actions on malware detections. If you disable or do not configure this policy setting Windows Defender Antivirus will prompt users to take actions on malware detections.

Check content

Verify the policy value for Computer Configuration -> Administrative Templates -> Windows Components -> Windows Defender Antivirus -> Real-time Protection -> "Turn off real-time protection" is set to "Disabled" or "Not Configured". Procedure: Use the Windows Registry Editor to navigate to the following key: HKLM\Software\Policies\Microsoft\Windows Defender\Real-Time Protection Criteria: If the value "DisableRealtimeMonitoring" is REG_DWORD = 0, this is not a finding. If the value does not exist, this is not a finding. If the value is 1, this is a finding.

Fix text

Set the policy value for Computer Configuration -> Administrative Templates -> Windows Components -> Windows Defender Antivirus -> Real-time Protection -> "Turn off real-time protection" to "Disabled" or "Not Configured".

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