						unset($return[$key]);
				}
			}
			break;
	}
	return @array_change_key_case($return, CASE_UPPER);
}
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.