[39158] in bugtraq
URL-Encoding Problem in Finjan SurfinGate
daemon@ATHENA.MIT.EDU (=?UTF-8?B?RGFuaWVsIFNjaHLDtnRlcg==)
Tue Jun 14 14:34:50 2005
Message-ID: <42AEE8BA.4070707@gmx.de>
Date: Tue, 14 Jun 2005 16:24:58 +0200
From: =?UTF-8?B?RGFuaWVsIFNjaHLDtnRlcg==?= <d.schroeter@gmx.de>
MIME-Version: 1.0
To: bugtraq@securityfocus.com
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
SUMMARY
- -------
The Finjan SurfinGate use web content filtering and internet access
management for protecting the network.
A vulnerability in the product allows you to bypass the access
management. You can download files which are normally blocked.
VERSIONS AFFECTED
- -----------------
Tested with SurfinGate Version 7.0SP2 and SP3 (and maybe others...)
DETAILS
- -------
A URL ASCII decode problem exists in the Finjan SurfinGate. If you use
ASCII encoding for a not allowed file the Finjan SufinGate can not block
it. Mostly it's enough to convert the dots to '%2e'. For example: you
can bypass a not allowed EXE-download or a double extension file like
file.jpg.exe.
If you block the content type of the file you can not bypass the Finjan
SurfinGate. But a hacker will not use a correct configured webserver for
infiltrate files in the company....
Finjan Software Ltd. has been notified for one year!
Proof of concept
- ----------------
(This example will not work if you block the content type in your
infrastructure, but there are some webservers out there with a wrong
content type for EXE-files.....)
Of course we don't take a normal exe-file. Let us use a screensaver.
If you block SCR-files the following will be blocked:
http://www.mustangworld.com/ourpics/sware/Mustangworld.scr
If you _just_ block the SCR-extension (and not the content type in you
infrastructure) your can bypass the Finjan SurfinGate with the following
link:
http://www.mustangworld.com/ourpics/sware/Mustangworld%2escr
Bye
Daniel Schröter
- --
=========================================================
(gnu)PGP signierter Key vom heise c't Magazin verfügbar.
http://www.heise.de/security/dienste/pgp/
=========================================================
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.1 (GNU/Linux)
Comment: Using GnuPG with Thunderbird - http://enigmail.mozdev.org
iD8DBQFCrui60uIOmJO/NdERAgdAAKDo1xRPO/tXiiRkW1hL5oP53PUrYACfWS2u
kF8l2cInyHrWPaVqZouWnkg=
=k0Mw
-----END PGP SIGNATURE-----
