Windows Defender AV must be configured to scan all downloaded files and attachments.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-75225	WNDF-AV-000020	SV-89905r2_rule		Medium

Description
This policy setting allows you to configure scanning for all downloaded files and attachments. If you enable or do not configure this setting scanning for all downloaded files and attachments will be enabled. If you disable this setting scanning for all downloaded files and attachments will be disabled.

STIG	Date
Windows Defender Antivirus Security Technical Implementation Guide	2017-12-27

Details

Check Text ( C-75017r3_chk )
Verify the policy value for Computer Configuration -> Administrative Templates -> Windows Components -> Windows Defender Antivirus -> Real-time Protection -> "Scan all downloaded files and attachments" 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 "DisableIOAVProtection" 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.

Check Text ( C-75017r3_chk )

Verify the policy value for Computer Configuration -> Administrative Templates -> Windows Components -> Windows Defender Antivirus -> Real-time Protection -> "Scan all downloaded files and attachments" 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 "DisableIOAVProtection" 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 (F-81835r2_fix)
Set the policy value for Computer Configuration -> Administrative Templates -> Windows Components -> Windows Defender Antivirus -> Real-time Protection -> "Scan all downloaded files and attachments" to "Enabled" or "Not Configured".