[REQ-END-150] Audit Policy: System Events Auditing for Endpoints

Target Scope

• Applicable Systems: Tier 2 Client Workstations
• Operating Systems: Windows 10/11 Enterprise/Professional

Implementation Details

• Priority: High
• GPO Path / Registry Location:
  • GPO Paths: Computer Configuration\Policies\Windows Settings\Security Settings\Advanced Audit Policy Configuration\Audit Policies
  • Subcategory: Other System Events -> Success and Failure
  • Subcategory: Security State Change -> Success and Failure
  • Subcategory: Security System Extension -> Success and Failure
  • Subcategory: System Integrity -> Success and Failure

Rationale

Auditing system security extensions, integrity violations, and driver arrivals monitors boot health and tampering of host security services.

Legacy Impact & Compatibility

• Event Log Volume: Set local Security Event Log size to a minimum of 512MB to prevent premature rollover of security auditing data.

Implementation Steps

Option A: Group Policy Object (GPO) Configuration (Preferred)

1. Configure Advanced Audit Policy subcategory or registry override preferences matching:
   • Subcategory: Other System Events -> Success and Failure
   • Subcategory: Security State Change -> Success and Failure
   • Subcategory: Security System Extension -> Success and Failure
   • Subcategory: System Integrity -> Success and Failure

Option B: PowerShell & Registry Configuration (Remediation / Non-GPO)

Download Script: Configure-EndAuditSystemevents.ps1

# Configure-EndAuditSystemevents.ps1
Write-Host "Applying Audit Policy category: system-events..." -ForegroundColor Cyan

# Set Audit Subcategory: Other System Events
$Process = Start-Process auditpol -ArgumentList "/set /subcategory:`"Other System Events`" /success:enable /failure:enable" -Wait -NoNewWindow -PassThru
if ($Process.ExitCode -eq 0) {
    Write-Host "    Enforced subcategory Other System Events to Success and Failure" -ForegroundColor Green
} else {
    Write-Error "    Failed to configure subcategory Other System Events. Exit Code: $($Process.ExitCode)"
}

# Set Audit Subcategory: Security State Change
$Process = Start-Process auditpol -ArgumentList "/set /subcategory:`"Security State Change`" /success:enable /failure:enable" -Wait -NoNewWindow -PassThru
if ($Process.ExitCode -eq 0) {
    Write-Host "    Enforced subcategory Security State Change to Success and Failure" -ForegroundColor Green
} else {
    Write-Error "    Failed to configure subcategory Security State Change. Exit Code: $($Process.ExitCode)"
}

# Set Audit Subcategory: Security System Extension
$Process = Start-Process auditpol -ArgumentList "/set /subcategory:`"Security System Extension`" /success:enable /failure:enable" -Wait -NoNewWindow -PassThru
if ($Process.ExitCode -eq 0) {
    Write-Host "    Enforced subcategory Security System Extension to Success and Failure" -ForegroundColor Green
} else {
    Write-Error "    Failed to configure subcategory Security System Extension. Exit Code: $($Process.ExitCode)"
}

# Set Audit Subcategory: System Integrity
$Process = Start-Process auditpol -ArgumentList "/set /subcategory:`"System Integrity`" /success:enable /failure:enable" -Wait -NoNewWindow -PassThru
if ($Process.ExitCode -eq 0) {
    Write-Host "    Enforced subcategory System Integrity to Success and Failure" -ForegroundColor Green
} else {
    Write-Error "    Failed to configure subcategory System Integrity. Exit Code: $($Process.ExitCode)"
}

To audit the hardening status: Download Script: Get-EndAuditSystemeventsStatus.ps1

# Get-EndAuditSystemeventsStatus.ps1
$script:Vulnerable = $false

# Audit Subcategory: Other System Events
$RawOutput = auditpol.exe /get /subcategory:"Other System Events" /r
if ($RawOutput -notmatch ",Other System Events,.*,(Success and Failure|Success & Failure)") {
    $script:Vulnerable = $true
}

# Audit Subcategory: Security State Change
$RawOutput = auditpol.exe /get /subcategory:"Security State Change" /r
if ($RawOutput -notmatch ",Security State Change,.*,(Success and Failure|Success & Failure)") {
    $script:Vulnerable = $true
}

# Audit Subcategory: Security System Extension
$RawOutput = auditpol.exe /get /subcategory:"Security System Extension" /r
if ($RawOutput -notmatch ",Security System Extension,.*,(Success and Failure|Success & Failure)") {
    $script:Vulnerable = $true
}

# Audit Subcategory: System Integrity
$RawOutput = auditpol.exe /get /subcategory:"System Integrity" /r
if ($RawOutput -notmatch ",System Integrity,.*,(Success and Failure|Success & Failure)") {
    $script:Vulnerable = $true
}

if ($script:Vulnerable) {
    Write-Output "Non-Compliant"
    exit 1
} else {
    Write-Output "Compliant"
    exit 0
}

Sources & Compliance References

• ANSSI Active Directory Hardening Guide: Client auditing baselines
• CIS Windows 10/11 Benchmark: Section 17 (Advanced Audit Policy Configuration)