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 hotfix to fix this vulnerability
in IMail Server 8.15:
ftp://ftp.ipswitch.com/Ipswitch/Product_Support/IMail/imail82hf2.exe
The vendor has released the following hotfix to fix this vulnerability
in IMail Server 8.2:
ftp://ftp.ipswitch.com/Ipswitch/Product_Support/IMail/imail82hf2.exe
The vendor has released the following hotfix to fix this vulnerability
in Ipswitch Collaboration Suite 2.0:
http://ftp.ipswitch.com/ipswitch/Product_Support/ICS/ICS2hf2.exe
The associated vendor advisories are available at:
http://www.ipswitch.com/Support/imail/releases/imail_professional/im81
5hf2.html
http://www.ipswitch.com/support/imail/releases/imail_professional/im82
hf2.html
http://www.ipswitch.com/Support/ICS/updates/ics2hf2.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 © 2005 iDEFENSE, Inc.
Permission is granted for the redistribution of this alert
electronically. It may not be edited in any way without the express
written consent of iDEFENSE. If you wish to reprint the whole or any
part of this alert in any other medium other than electronically, please
email customerservice@idefense.com for permission.
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.
