first delete the file name ( install )
than protect ur files with password from ur cpanel
( admincp )
( modcp )
( includes )
and when u do all this setup ur Vb well be ok.

but there is some place u need to fixed 2
first check the ( editpost.php ) on the top after this word ( put this code
--------------------------------------------------------------------------
  $title = addslashes($title);
if (strstr($title,"script") != NULL){
  echo "hello.. are you hacking us?
vBulletin
note: use scr!pt";
  exit;
}
--------------------------------------------------------------------------
and save the setting second open this file 2 ( subscriptions/authorize.php )
and find this code
------------------------------------------------------------------------
$userid = $DB_site->query_first("SELECT userid, languageid, styleid FROM " . TABLE_PREFIX . "user WHERE userid = " . $item_number[1]);
--------------------------------------------------------------------------
and remove it and put this new code
--------------------------------------------------------------------------
 $userid = $DB_site->query_first("SELECT userid, languageid, styleid FROM " .
TABLE_PREFIX . "user WHERE userid = " .intval( $item_number[1]));  
--------------------------------------------------------------------------

now ur Vb is safe from any hacking and have fun all ^.^