SIG^2 Vulnerability Research Advisory

SurgeMail Webmail Attachment Upload and XSS Vulnerabilities

by Tan Chew Keong
Release Date: 23 Mar 2005

ADVISORY URL
http://www.security.org.sg/vuln/surgemail22g3.html


SUMMARY

SurgeMail (http://netwinsite.com/surgemail/) is a next generation Mail Server - Combining features, performance and ease of use into a single integrated product. Ideal on Windows NT/2K, or UNIX (Linux, Solaris etc) and supports all the standard protocols IMAP, POP3, SMTP, SSL, ESMTP.

A vulnerability was found in SurgeMail's Webmail file attachment upload feature. This vulnerability may be exploited by a malicious Webmail user to upload files to certain locations on the server, obtain file listings of certain directories, and/or send certain files on the server to him/herself. Two XSS vulnerabilities were also found. 
 

TESTED SYSTEM

SurgeMail Version 2.2g3 Windows on English Win2K SP4.

 
DETAILS

This advisory document two Webmail vulnerabilities found in SurgeMail server. The first is a file attachment upload vulnerability. This vulnerability may be exploited by a malicious Webmail user to upload files to certain locations on the server, obtain file listings of certain directories, and/or send certain files on the server to him/herself. The second is a Cross-Site Scripting (XSS) vulnerability.

1. File Attachment Upload Vulnerability.
 
SurgeMail allows a logon user to attach files when composing a new email via the Webmail interface. Uploaded file attachments are temporarily stored in the c:\surgemail\web_work\u_xx\xxxx@hostname@127_0_0_1\attach\SomeRandomNumber\ directory. In particular, the value of SomeRandomNumber is part of this POST request (attach_id parameter) and is under the attacker's control. The server will create the directory "SomeRandomNumber" if it does not exist. By using directory traversal characters, it is possible to cause the uploaded files to be written to other directories.

2. Cross-Site Scripting (XSS) Vulnerabilities.

A user is allowed to configure an email auto-reply message using the Webmail interface. This auto-reply message consist of a message subject and a message header. It is possible to inject javascript in both these fields. If the Webmail administrator views this user's auto-reply message settings, the injected javascript will be executed on his browser. This may be exploited by a malicious user to steal the Webmail administrator's cookies or to redirect the administrator's browser to malicious websites.

Another XSS vulnerability occurs when webmail.exe is displaying an error message in response to an invalid value in the page parameter. The error message also reveals the installation path.


PATCH

Upgrade to the latest version of SurgeMail (Version 3.0c2 or later).

 
DISCLOSURE TIMELINE

18 Mar 05 - Vulnerability Discovered.
19 Mar 05 - Vulnerability Verification.
19 Mar 05 - Initial Vendor Notification.
22 Mar 05 - Vendor replied with fixed version.
23 Mar 05 - Public Release.
 

GREETINGS

All guys at SIG^2 G-TEC Lab
http://www.security.org.sg/webdocs/g-tec.html 

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