Title

The Microsoft Defender SmartScreen for Explorer must be enabled. (Cat II impact)

Discussion

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.

Check Content

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

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.

Additional Identifiers

Rule ID: SV-253395r958478_rule

Vulnerability ID: V-253395

Group Title: SRG-OS-000095-GPOS-00049

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.