    public static function incBack($vars)
    {
        $file = GX_PATH.'/inc/lib/Control/Backend/'.$vars.'.control.php';
        if (file_exists($file)) {
            # code...
            include $file;
        } else {
            self::error('404');
        }
    }
The software constructs all or part of an SQL command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended SQL command when it is sent to a downstream component.