Microsoft Defender AV must be configured to enable behavior monitoring.

Severity	Group ID	Group Title	Version	Rule ID	Date	STIG Version
medium	V-213446	SRG-APP-000210	WNDF-AV-000022	SV-213446r823063_rule	2022-04-08	2

Description
This policy setting allows configuration of behavior monitoring. If this setting is enabled or not configured, behavior monitoring will be enabled. If this setting is disabled, behavior monitoring will be disabled.

ℹ️ Check
Verify the policy value for Computer Configuration >> Administrative Templates >> Windows Components >> Microsoft Defender Antivirus >> Real-time Protection >> "Turn on behavior monitoring" is set to "Enabled" 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 "DisableBehaviorMonitoring" 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.

ℹ️ Check

Verify the policy value for Computer Configuration >> Administrative Templates >> Windows Components >> Microsoft Defender Antivirus >> Real-time Protection >> "Turn on behavior monitoring" is set to "Enabled" 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 "DisableBehaviorMonitoring" 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
Set the policy value for Computer Configuration >> Administrative Templates >> Windows Components >> Windows Defender Antivirus >> Real-time Protection >> "Turn on behavior monitoring" to "Enabled " or "Not Configured".