id: powershell-script-block-logging-disabled

info:
  name: PowerShell Script Block Logging - Disabled
  author: JeonSungHyun[nukunga]
  severity: medium
  description: |
    Disabling script block logging reduces visibility into executed scripts, making it harder to detect and investigate malicious PowerShell activity.
  reference:
    - https://www.elastic.co/guide/en/security/7.17/prebuilt-rule-0-16-1-powershell-script-block-logging-disabled.html
  impact: |
    Lack of script block logging allows malicious PowerShell activity to go unnoticed, increasing security risks and reducing forensic capabilities.
  remediation: |
    Enable PowerShell script block logging in Group Policy or Registry.
  tags: windows,powershell,audit,code

self-contained: true

code:
  - pre-condition: |
      IsWindows();

    engine:
      - powershell
      - powershell.exe

    args:
      - -ExecutionPolicy
      - Bypass

    pattern: "*.ps1"

    source: |
      $regPath = "HKLM:\Software\Policies\Microsoft\Windows\PowerShell\ScriptBlockLogging"
      $logValue = (Get-ItemProperty -Path $regPath -Name "EnableScriptBlockLogging" -ErrorAction SilentlyContinue).EnableScriptBlockLogging
      if ($logValue -ne 1) {
        Write-Output "PowerShell Script Block Logging is disabled!"
      }

    matchers:
      - type: word
        words:
          - "PowerShell Script Block Logging is disabled!"