Title

Microsoft Defender AV must enable asynchronous inspection. (Cat II impact)

Discussion

Network protection includes performance optimization that allows block mode to asynchronously inspect long-lived connections, which might provide a performance improvement. This optimization can also help with app compatibility problems.

Check Content

Verify the policy value for Computer Configuration >> Administrative Templates >> Windows Components >> Microsoft Defender Antivirus >> Network Inspection System >> Turn on asynchronous inspection is set to "Enabled"; otherwise, this is a finding. Procedure: Use the Windows Registry Editor to navigate to the following key: HKLM\Software\Policies\Microsoft\Windows Defender\NIS Criteria: If the value "AllowSwitchToAsyncInspection" is REG_DWORD = 1, this is not a finding. If the value is 0, this is a finding.

Fix Text

Set the policy value for Computer Configuration >> Administrative Templates >> Windows Components >> Microsoft Defender Antivirus >> MpEngine >> Turn on asynchronous inspection to "Enabled". Click "OK". Click "Apply".

Additional Identifiers

Rule ID: SV-278678r1144079_rule

Vulnerability ID: V-278678

Group Title: SRG-APP-000210

Expert Comments

CCIs tied to check.

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