Microsoft Defender AV must enable asynchronous inspection.

Overview

Finding IDVersionRule IDIA ControlsSeverity
V-278678WNDF-AV-000075SV-278678r1190771_ruleCCI-001170medium
Description
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.
STIGDate
Microsoft Defender Antivirus Security Technical Implementation Guide2026-02-17

Details

Check Text (C-278678r1190771_chk)

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 (F-83117r1190770_fix)

Set the policy value for Computer Configuration >> Administrative Templates >> Windows Components >> Microsoft Defender Antivirus >> Network Inspection System >> Turn on asynchronous inspection to "Enabled".