-- Corsaire Security Advisory --

Title: Mitel 3300 ICP web interface session hijacking issue
Date: 17.08.04
Application: Mitel Web Management Interface
Environment: Mitel 3300 ICP (prior to 4.2.2.11)
Author: Stephen de Vries [stephen@corsaire.com]
Audience: General distribution
Reference: c040817-002


-- Scope --

The aim of this document is to define a vulnerability in the 3300 
Integrated Communication Platform as supplied by Mitel [1], that allows 
a remote attacker to hijack legitimate users' web management sessions.


-- History --

Discovered: 17.08.04 (Stephen de Vries)
Vendor notified: 27.08.04
Document released: 28.02.05


-- Overview --

The 3300 ICP [2] provides enterprise IP-PBX capabilities and makes use 
of a Web Interface to manage the device.  In order to maintain a user 
session, the Web Interface generates a unique session ID for each user 
after they have successfully authenticated.  Once the client has 
authenticated, this session ID is used as a shared secret to 
authenticate the client to the server for all subsequent requests. 
This session ID was found to be trivially predictable and allows 
attackers to hijack legitimate users' sessions.


-- Analysis --

The Web Interface on the 3300 ICP generates the session ID after 
successful authentication.  The HTML page returned after successful 
authentication contains Javascript code that sets a cookie with the name 
"parentsessionid" to the value of the session ID.  By making successive 
authentication requests a list of session IDs can be retrieved.  A 
random sample follows:

parentsessionid=3
parentsessionid=4
parentsessionid=5
parentsessionid=6
parentsessionid=7
parentsessionid=8
parentsessionid=9
parentsessionid=10
parentsessionid=11
parentsessionid=12

It is quite clear that these IDs are sequential.  Further investigation 
revealed that the Web Interface has an upper limit of 50 active session 
IDs.  This further reduces the number of IDs that an attacker has to 
guess before being able to hijack a user's session.


-- Recommendations --

The vendor has released a revised version of the software that does not 
exhibit this issue. This has not been independently verified by 
Corsaire.


-- CVE --

The Common Vulnerabilities and Exposures (CVE) project has assigned the 
name CAN-2004-0944 to this issue. This is a candidate for inclusion in 
the CVE list (http://cve.mitre.org), which standardises names for 
security problems.


-- References --

[1] http://www.mitel.com
[2] http://www.mitel.com/DocController?documentId=9555&c=9511&sc=9514


-- Revision --

a. Initial release.
b. Minor revision.


-- Distribution --

The information contained within this advisory is supplied "as-is" with 
no warranties or guarantees of fitness of use or otherwise. Corsaire 
accepts no responsibility for any damage caused by the use or misuse of 
this information.


-- Disclaimer --

The information contained within this advisory is supplied "as-is" with 
no warranties or guarantees of fitness of use or otherwise. Corsaire 
accepts no responsibility for any damage caused by the use or misuse of 
this information.


-- About Corsaire --

Corsaire are a leading information security consultancy, founded in 1997 
in Guildford, Surrey, UK. Corsaire bring innovation, integrity and 
analytical rigour to every job, which means fast and dramatic security 
performance improvements. Our services centre on the delivery of 
information security planning, assessment, implementation, management 
and vulnerability research. 

A free guide to selecting a security assessment supplier is available at 
http://www.penetration-testing.com 


Copyright 2004-2005 Corsaire Limited. All rights reserved.