Ipswitch IMail IMAP STATUS Remote Buffer Overflow Vulnerability

iDEFENSE Security Advisory 05.24.05
www.idefense.com/application/poi/display?id=244&type=vulnerabilities
May 24, 2005

I. BACKGROUND

Ipswitch Collaboration Suite (ICS) is a comprehensive communication and 
collaboration solution for Microsoft Windows with a customer base of 
over 53 million users. More information is available on the vendor's 
website:

     http://www.ipswitch.com/products/IMail_Server/index.html

II. DESCRIPTION

Remote exploitation of a buffer overflow vulnerability in Ipswitch 
Inc.'s Imail IMAP server allows attackers to execute arbitrary code with

System privileges. 

The vulnerability specifically exists in the handling of a long mailbox 
name to the STATUS command. A long mailbox name argument will cause a 
stack based buffer overflow, providing the attacker with full control 
over the saved return address on the stack. Once this has been achieved,

execution of arbitrary code becomes trivial. As this vulnerability is in

the STATUS command, which requires that a session is authenticated, 
valid credentials are required.

III. ANALYSIS

Successful exploitation allows remote attackers to execute arbitrary 
code with System privileges. Valid credentials are required for 
exploitation, which lessens the impact of this vulnerability.

IV. DETECTION

iDEFENSE has confirmed the existence of this vulnerability in Ipswitch 
IMail version 8.13. It is suspected that earlier versions are also 
vulnerable.

V. WORKAROUND

As this vulnerability is exploited after authentication occurs, ensuring

that only trusted users have accounts can mitigate the risk somwhat. As 
a more effective workaround, consider limiting access to the IMAP server

by filtering TCP port 143. If possible, consider disabling IMAP and 
forcing users to use POP3.

VI. VENDOR RESPONSE

The vendor has released the following patch to fix this vulnerability:

ftp://ftp.ipswitch.com/Ipswitch/Product_Support/IMail/imail82hf2.exe

The associated vendor advisory can be found at:

http://www.ipswitch.com/support/imail/releases/imail_professional/im82hf
2.html

VII. CVE INFORMATION

The Common Vulnerabilities and Exposures (CVE) project has assigned the
name CAN-2005-1256 to this issue. This is a candidate for inclusion in
the CVE list (http://cve.mitre.org), which standardizes names for
security problems.

VIII. DISCLOSURE TIMELINE

04/25/2005  Initial vendor notification
05/10/2005  Initial vendor response
05/24/2005  Public disclosure

IX. CREDIT

iDEFENSE Labs is credited with this discovery.

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X. LEGAL NOTICES

Copyright (c) 2005 iDEFENSE, Inc.

Permission is granted for the redistribution of this alert
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Disclaimer: The information in the advisory is believed to be accurate
at the time of publishing based on currently available information. Use
of the information constitutes acceptance for use in an AS IS condition.
There are no warranties with regard to this information. Neither the
author nor the publisher accepts any liability for any direct, indirect,
or consequential loss or damage arising from use of, or reliance on,
this information.