Novell NetMail NMDMC Buffer Overflow Vulnerability

iDefense Security Advisory 05.10.07
http://labs.idefense.com/intelligence/vulnerabilities/
May 10, 2007

I. BACKGROUND

Novell Inc.'s NetMail is an e-mail and calendar system that is based on
standard Internet protocols. More information can be found at the URL
shown below.

http://www.novell.com/products/netmail/

II. DESCRIPTION

Remote exploitation of a buffer overflow vulnerability within Novell
Inc.'s NetMail allows attackers to execute arbitrary code with the
privileges of the service.

This vulnerability specifically exists within the SSL version of the
"NMDMC.EXE" service. The application does not perform sufficient input
validation when copying data into a fixed size stack buffer. When
processing a specially crafted request made to this service, a
stack-based buffer overflow occurs leading to corruption of program
control registers saved on the stack.

III. ANALYSIS

Exploitation allows attackers to execute code in the context of the
running service. By default this service runs with the privileges of
"NetMailService".

No authentication is required to reach the vulnerable code.
Additionally, this is an SSL based service which complicates writing
IDS signatures.

It appears that the non-SSL version of this service is not vulnerable.

IV. DETECTION

iDefense has confirmed the existence of this vulnerability within
version 3.52e_FTF2 of Novell Inc's NetMail. Older versions are
suspected to be vulnerable.

V. WORKAROUND

Employ firewalls to minimize the exposure of this service.

VI. VENDOR RESPONSE

Novell has addressed this vulnerability in the beta release of Novell
NetMail 3.52f. For more information, consult the document located at
the following URL.

http://download.novell.com/Download?buildid=Ad2xk29hHTg~

VII. CVE INFORMATION

A Mitre Corp. Common Vulnerabilities and Exposures (CVE) number has not
been assigned yet.

VIII. DISCLOSURE TIMELINE

02/07/2007  Initial vendor notification
02/08/2007  Initial vendor response
05/10/2007  Public disclosure

IX. CREDIT

The discoverer of this vulnerability wishes to remain anonymous.

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X. LEGAL NOTICES

Copyright © 2007 iDefense, Inc.

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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
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