I. BACKGROUND
Novell eDirectory is a cross-platform lightweight directory access
protocol (LDAP) server. More information can be found on Novell's
web site at http://www.novell.com/products/edirectory/
II. DESCRIPTION
Remote exploitation of a heap overflow vulnerability in Novell Inc.'s
eDirectory product could allow an attacker to execute arbitrary code in
the context of the running daemon.
This problem stems from an integer overflow that occurs when allocating
memory for attacker supplied data. The evtFilteredMonitorEventsRequest
function takes user input and multiplies it by 16, then adds 16 without
first validating that an integer overflow will not occur. If allocation
succeeds, the function will proceed to loop, filling the memory with
partially controllable input. Since the loop is bounded directly by the
attacker supplied length value, heap overflow will occur.
III. ANALYSIS
Successful exploitation of this vulnerability could allow an attacker to
crash the server or execute arbitrary code. No credentials are required.
Typically this daemon runs with administrator privileges.
IV. DETECTION
iDefense has confirmed the existence of this vulnerability in version
8.8.1 of Novell Inc.'s eDirectory server. Version 8.8 was also tested
and found to be vulnerable. Earlier versions are suspected to be
vulnerable.
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 program.
VI. VENDOR RESPONSE
Novell has addressed this vulnerability with eDirectory 8.8.1 FTF1.
You can obtain the Linux/Unix version of this update from their site at:
http://support.novell.com/servlet/filedownload/sec/pub/edir881ftf_1.tg
z/
The windows version of this update is available at:
http://support.novell.com/servlet/filedownload/sec/pub/edir881ftf_1.ex
e/
VII. CVE INFORMATION
The Common Vulnerabilities and Exposures (CVE) project has assigned the
name CVE-2006-4509 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
08/17/2006 Initial vendor notification
08/18/2006 Initial vendor response
10/06/2006 Second vendor notification
10/20/2006 Vendor update released
10/21/2006 Public disclosure
IX. CREDIT
The discoverer of this vulnerability wishes to remain anonymous.
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X. LEGAL NOTICES
Copyright © 2006 iDefense, Inc.
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Disclaimer: The information in the advisory is believed to be
accurate
at the time of
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of the
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There are no warranties with
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Neither the
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