iDefense Security Advisory 07.09.08
http://labs.idefense.com/intelligence/vulnerabilities/
Jul 09, 2008

I. BACKGROUND

Novell eDirectory is cross-platform directory server that implements the
Lightweight Directory Access Protocol (LDAP). The search request is used
to search a directory tree for objects that match a search filter. For
more information, see the vendor's site found at the following URL.

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

II. DESCRIPTION

Remote exploitation of a heap buffer overflow vulnerability in Novell
Inc.'s eDirectory could allow an attacker to execute arbitrary code
with the privileges of the affected service.

The vulnerability exists due to an incorrect calculation when allocating
a heap buffer to store the search parameters. By passing NULL search
parameters, it is possible to overflow a heap based buffer with the
string "(null)". This can result in the corruption of heap management
structures, and depending on the layout of the heap, possibly function
pointers.

III. ANALYSIS

Exploitation of this vulnerability results in the execution of arbitrary
code with the privileges of the affected service, usually root. Since
the data that overflows the buffer is not controlled by the attacker,
exploitation is non-trivial.

IV. DETECTION

iDefense has confirmed the existence of this vulnerability in eDirectory
version 8.8 SP2 for Linux. Other versions may also be affected.

V. WORKAROUND

It is possible to disable the LDAP service from running via the
ndsmodules.conf file which is usually located in
/etc/opt/novell/eDirectory/conf. However, doing so greatly reduces the
functionality of this software.

VI. VENDOR RESPONSE

Novell Inc. has addressed this vulnerability with the release of FTF2
for eDirectory 8.8 SP2 (8.8.2) and SP10b for eDirectory 8.7.3. For more
information visit the following URL.

http://www.novell.com/support/viewContent.do?externalId=3843876

VII. CVE INFORMATION

The Common Vulnerabilities and Exposures (CVE) project has assigned the
name CVE-2008-1809 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

03/10/2008  Initial vendor notification
03/13/2008  Initial vendor response
07/09/2008  Coordinated public disclosure

IX. CREDIT

The discoverer of this vulnerability wishes to remain anonymous.

Get paid for vulnerability research
http://labs.idefense.com/methodology/vulnerability/vcp.php

Free tools, research and upcoming events
http://labs.idefense.com/

X. LEGAL NOTICES

Copyright © 2008 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 e-mail 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.