Microsoft Defender AV must block credential stealing from the Windows local security authority subsystem.

Severity	Group ID	Group Title	Version	Rule ID	Date	STIG Version
medium	V-278648	SRG-APP-000210	WNDF-AV-000044	SV-278648r1144032_rule	2025-11-25	2

Description
This policy setting helps prevent credential stealing by locking down Local Security Authority Subsystem Service (LSASS).

ℹ️ Check
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". 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 "9e6c4e1f-7d60-472f-ba1a-a39ef669e4b2" is REG_SZ = 1, this is not a finding. If the value is other than 1, this is a finding.

ℹ️ Check

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". 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 "9e6c4e1f-7d60-472f-ba1a-a39ef669e4b2" is REG_SZ = 1, this is not a finding. If the value is other than 1, this is a finding.

✔️ Fix
Set 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 to "Enabled". Under the policy option "Set the state for each ASR rule:", then click "Show". Enter GUID "9e6c4e1f-7d60-472f-ba1a-a39ef669e4b2" in the "Value Name" column. Enter "1" in the "Value" column. Click "OK". Click "Apply".

✔️ Fix

Set 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 to "Enabled". Under the policy option "Set the state for each ASR rule:", then click "Show". Enter GUID "9e6c4e1f-7d60-472f-ba1a-a39ef669e4b2" in the "Value Name" column. Enter "1" in the "Value" column. Click "OK". Click "Apply".