    protected function parseChunkedRequest(Request $request)
    {
        $index = $request->get('qqpartindex');
        $total = $request->get('qqtotalparts');
        $uuid = $request->get('qquuid');
        $orig = $request->get('qqfilename');
        $last = ((int) $total - 1) === (int) $index;

        return [$last, $uuid, $index, $orig];
    }
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.