source: https://www.securityfocus.com/bid/10658/info

The NetFile FTP/Web Server is reported prone to a directory traversal vulnerability due to insufficient sanitization of user-supplied data. This can allow an attacker to create, view, and delete arbitrary files outside the web root.

Fastream NetFILE FTP/Web Server versions 6.7.2.1085 and prior are reported prone to this issue.

http://www.example.com?command=mkdir&filename=..//FOLDER_IS_OUTSIDE_THE_ROOT_DIRECTORY