[NT] Cross-Site Scripting Issues in Falcon Web Server

From: support@securiteam.com
Date: 08/10/02

From: support@securiteam.com
To: list@securiteam.com
Date: Sat, 10 Aug 2002 22:29:54 +0200 (CEST)

The following security advisory is sent to the securiteam mailing list, and can be found at the SecuriTeam web site: http://www.securiteam.com
- - promotion

When was the last time you checked your server's security?
How about a monthly report?
http://www.AutomatedScanning.com - Know that you're safe.
- - - - - - - - -

  Cross-Site Scripting Issues in Falcon Web Server


Falcon Web Server is running under Windows NT/2000/XP as well as Windows
95/98. It supports ISAPI and WinCGI, and it is a fully functional web
server that is capable of running a small / medium scale website of about
50-80 hits per minute. The real advantage of Falcon Web Server is the
ability to run on a desktop computer with almost the same functionality as
large-scale web servers like MS IIS and Apache. A lack of input sanitation
in the error message output of this server makes it susceptible to two
cross-site scripting vulnerabilities.


Vulnerable systems:
 * BlueFace Falcon Web Server 1.0
 * BlueFace Falcon Web Server 1.0.01008

Technical details:
The following two issues exist:

* An issue in the way the server handles 301 messages when a file is not
found, and the request is not terminated by a slash. Falcon simply adds a
slash to the requested URI, and sends back a 301 with the following

<html><head><title>/<SCRIPT>alert("xss")</SCRIPT>/</title></head><body>Redirecting browser to <ahref="/<SCRIPT>alert("xss")</SCRIPT>/">/<SCRIPT>alert("xss")</SCRIPT>/</a><br>If nothing happens click the link above.</body></html>

* An issue in the way the server handles 404 messages when a file/folder
is not found, and the necessary slash has been added (entity below):

<html><head><title>HTTP/1.0 404 Not
Not Found</h1><p>Cannot locate the requested file.</body></html>

* 301 Message XSS

Closing TITLE tag:

Closing A HREF:

Closing A tag:

* 404 Message XSS

The 301 examples will simply add a slash and pass it on to the browser,
which then raises a 404, exploiting that vulnerability as well (although
the 301 exploits will cause some useless HTML to be added on).


The information has been provided by <mailto:mattmurphy@kc.rr.com>
Matthew Murphy.


This bulletin is sent to members of the SecuriTeam mailing list.
To unsubscribe from the list, send mail with an empty subject line and body to: list-unsubscribe@securiteam.com
In order to subscribe to the mailing list, simply forward this email to: list-subscribe@securiteam.com


The information in this bulletin is provided "AS IS" without warranty of any kind.
In no event shall we be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages.