source: https://www.securityfocus.com/bid/9053/info

It has been reported that phpWebFileManager may be prone to a directory traversal vulnerability that may allow an attacker to gain access to sensitive information. The issue presents itself due to insufficient sanitization of user-supplied input. An attacker may traverse outside the server root directory by using '../' character sequences.

phpWebFileManager version 2.0.0 is reported to be prone to this issue, however other versions may be affected as well. 

http://www.example.com/phpwebfilemgr/index.php?f=../../../