Multiple directory traversal vulnerabilities in FTPServer.py in pyftpdlib before 0.2.0 allow remote authenticated users to access arbitrary files and directories via a .. (dot dot) in a (1) LIST, (2) STOR, or (3) RETR command.
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.