Microsoft Defender AV must be configured to block executable content from email client and webmail.

Overview

Finding IDVersionRule IDIA ControlsSeverity
V-213456WNDF-AV-000032SV-213456r823081_ruleCCI-001170medium
Description
This rule blocks the following file types from being run or launched from an email seen in either Microsoft Outlook or webmail (such as Gmail.com or Outlook.com): Executable files (such as .exe, .dll, or .scr) Script files (such as a PowerShell .ps, VisualBasic .vbs, or JavaScript .js file) Script archive files
STIGDate
Microsoft Defender Antivirus Security Technical Implementation Guide2022-04-08

Details

Check Text (C-213456r823081_chk)

This setting is applicable starting with v1709 of Windows 10. It is NA for prior versions. Verify the policy value for Computer Configuration >> Administrative Templates >> Windows Components >> Microsoft Defender Antivirus >> Microsoft Defender Exploit Guard >> Attack Surface Reduction >> "Configure Attack Surface Reduction rules" is set to "Enabled”. Click "Show...". Verify the rule ID in the Value name column and the desired state in the Value column is set as follows: Value name: BE9BA2D9-53EA-4CDC-84E5-9B1EEEE46550 Value: 1 Procedure: Use the Windows Registry Editor to navigate to the following key: HKLM\Software\Policies\Microsoft\Windows Defender\Windows Defender Exploit Guard\ASR\Rules Criteria: If the value "BE9BA2D9-53EA-4CDC-84E5-9B1EEEE46550" is REG_SZ = 1, this is not a finding.

Fix Text (F-14679r823080_fix)

Set the policy value for Computer Configuration >> Administrative Templates >> Windows Components >> Microsoft Defender Antivirus >> Windows Defender Exploit Guard >> Attack Surface Reduction >> "Configure Attack Surface Reduction rules" to "Enabled". Click "Show...". Set the Value name to "BE9BA2D9-53EA-4CDC-84E5-9B1EEEE46550" and the Value to "1".