Directory traversal vulnerability in Porta+ FTP Client 4.1, and possibly other versions, allows remote FTP servers to overwrite arbitrary files via a directory traversal sequences in a filename.
Improper Limitation of a Pathname to a Restricted Directory The product 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 product 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.