The Microsoft Defender SmartScreen for Explorer must be enabled.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-253395 | WN11-CC-000210 | SV-253395r958478_rule | CCI-000381 | medium |
| Description | ||||
| Microsoft Defender SmartScreen helps protect systems from programs downloaded from the internet that may be malicious. Enabling Microsoft Defender SmartScreen will warn or prevent users from running potentially malicious programs. | ||||
| STIG | Date | |||
| Microsoft Windows 11 Security Technical Implementation Guide | 2025-05-15 | |||
Details
Check Text (C-253395r958478_chk)
This is applicable to unclassified systems, for other systems this is NA.
If the following registry values do not exist or are not configured as specified, this is a finding:
Registry Hive: HKEY_LOCAL_MACHINE
Registry Path: \SOFTWARE\Policies\Microsoft\Windows\System\
Value Name: EnableSmartScreen
Value Type: REG_DWORD
Value: 0x00000001 (1)
And
Registry Hive: HKEY_LOCAL_MACHINE
Registry Path: \SOFTWARE\Policies\Microsoft\Windows\System\
Value Name: ShellSmartScreenLevel
Value Type: REG_SZ
Value: Block
Fix Text (F-56798r829268_fix)
Configure the policy value for Computer Configuration >> Administrative Templates >> Windows Components >> File Explorer >> "Configure Windows Defender SmartScreen" to "Enabled" with "Warn and prevent bypass" selected.
Windows 11 includes duplicate policies for this setting. It can also be configured under Computer Configuration >> Administrative Templates >> Windows Components >> Windows Defender SmartScreen >> Explorer.