function download_selected($dir)
{
    require_once("_include/fun_archive.php");
    $items = qxpage_selected_items();
    _download_items($dir, $items);
}
The software uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the software does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.