Windows Defender AV must be configured to scan removable drives.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-75235	WNDF-AV-000025	SV-89915r2_rule		Medium

Description
This policy setting allows you to manage whether or not to scan for malicious software and unwanted software in the contents of removable drives such as USB flash drives when running a full scan. If you enable this setting removable drives will be scanned during any type of scan. If you disable or do not configure this setting removable drives will not be scanned during a full scan. Removable drives may still be scanned during quick scan and custom scan.

Description

This policy setting allows you to manage whether or not to scan for malicious software and unwanted software in the contents of removable drives such as USB flash drives when running a full scan. If you enable this setting removable drives will be scanned during any type of scan. If you disable or do not configure this setting removable drives will not be scanned during a full scan. Removable drives may still be scanned during quick scan and custom scan.

STIG	Date
MS Windows Defender Antivirus Security Technical Implementation Guide	2020-05-12

Details

Check Text ( C-75027r2_chk )
Verify the policy value for Computer Configuration -> Administrative Templates -> Windows Components -> Windows Defender Antivirus -> Scan -> "Scan removable drives" is set to "Enabled". Procedure: Use the Windows Registry Editor to navigate to the following key: HKLM\Software\Policies\Microsoft\Windows Defender\Scan Criteria: If the value "DisableRemovableDriveScanning" is REG_DWORD = 0, this is not a finding.

Check Text ( C-75027r2_chk )

Verify the policy value for Computer Configuration -> Administrative Templates -> Windows Components -> Windows Defender Antivirus -> Scan -> "Scan removable drives" is set to "Enabled".

Procedure: Use the Windows Registry Editor to navigate to the following key:
HKLM\Software\Policies\Microsoft\Windows Defender\Scan

Criteria: If the value "DisableRemovableDriveScanning" is REG_DWORD = 0, this is not a finding.

Fix Text (F-81845r3_fix)
Set the policy value for Computer Configuration -> Administrative Templates -> Windows Components -> Windows Defender Antivirus -> Scan -> "Scan removable drives" to "Enabled".