TMA-DEFENDER-1.17
Ensure 'Control whether exclusions are visible to local users' is set to 'Enabled'
Description
This policy setting controls whether Microsoft Defender Antivirus exclusions are visible to local users on the system. The recommended state for this setting is: Enabled. Warning: This setting requires at least Microsoft Defender for Endpoint Plan 1 (Foundational enterprise endpoint protection) to function. If Plan 1 is not in use, an exception to this recommendation is required. Rationale: Only administrators should be able to view and manage Microsoft Defender Antivirus exclusions. Audit reads the Group Policy registry value and prints 'compliant', 'unset' (policy not configured, reported as FAIL) or the non-compliant value. Registry value: HKLM\SOFTWARE\Policies\Microsoft\Windows Defender:HideExclusionsFromLocalUsers (REG_DWORD); compliant when it is 1. Remediation writes 1 locally; in a domain set it through the ADMX so Group Policy does not revert it.
How it is checked
Audit method: Windows registry
$v = (Get-ItemProperty -Path 'Registry::HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows Defender' -Name 'HideExclusionsFromLocalUsers' -ErrorAction SilentlyContinue).'HideExclusionsFromLocalUsers'; if ($null -eq $v) { 'unset' } elseif (($null -ne $v -and @(1) -contains [int64]$v)) { 'compliant' } else { "non-compliant: $v" }- Expected output
compliant
How it is fixed
Fix method: Shell command
$p = 'Registry::HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows Defender'; if (-not (Test-Path -Path $p)) { New-Item -Path $p -Force | Out-Null }; New-ItemProperty -Path $p -Name 'HideExclusionsFromLocalUsers' -Value 1 -PropertyType DWord -Force | Out-NullProperties
- Operating systems
- Any
- Tags
- defenderantiviruscis-l1
- Reference
- CIS Microsoft Defender Antivirus Benchmark v1.0.0 - 1.17 Ensure 'Control whether exclusions are visible to local users' is set to 'Enabled'
Check this host
Run this on a machine you are allowed to audit. The scan is read-only.
tmaegis scan --target defender