SQL injection - GestDownV1.00Beta

[bebe@xxxxxxxxx]

catdownload.php (line 16)
$sql = ('SELECT * FROM downloads WHERE categorie='.$categorie.''); 

download.php (line 6)
mysql_query('SELECT * FROM `downloads`  WHERE categorie=' . $_GET['id']);

hitcounter.php (line 15)
$requete = "SELECT lien FROM downloads WHERE id=$id";


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