Protect yourself against future threats.
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
===========================================================================
AUSCERT External Security Bulletin Redistribution
ESB-2007.0274 -- [Win][Netware][UNIX/Linux]
Novell eDirectory NCP Fragment Denial of Service Vulnerability
27 April 2007
===========================================================================
AusCERT Security Bulletin Summary
---------------------------------
Product: Novell eDirectory 8.8.1 and prior
Publisher: iDefense
Operating System: Windows
Linux variants
Netware
Solaris
AIX
Impact: Denial of Service
Access: Remote/Unauthenticated
CVE Names: CVE-2006-4520
Original Bulletins:
http://labs.idefense.com/intelligence/vulnerabilities/display.php?id=518
http://www.novell.com/support/search.do?cmd=displayKC&externalId=3924657&sliceId=SAL_Public
- --------------------------BEGIN INCLUDED TEXT--------------------
Novell eDirectory NCP Fragment Denial of Service Vulnerability
iDefense Security Advisory 04.26.07
http://labs.idefense.com/intelligence/vulnerabilities/
Apr 26, 2007
I. BACKGROUND
Novell eDirectory is a cross-platform lightweight directory access
protocol (LDAP) server. In addition to LDAP, eDirectory also implements
NCP over IP. More information can be found on Novell's web site at the
following URL.
http://www.novell.com/products/edirectory/
II. DESCRIPTION
Remote exploitation of a denial of service (DoS) vulnerability in Novell
Inc.'s eDirectory product could allow an attacker to force the running
daemon to cease servicing requests.
The problem specifically exists within the NCP functionality of
eDirectory. Sending a sequence of specially crafted fragmented requests
will cause a DoS condition.
If the input is crafted properly, eDirectory will report to its error
log that a fragment has been received with an invalid length. The error
message includes the contents of the fragments in hexadecimal notation.
However, if the length is negative, eDirectory will try to dump data to
the log indefinitely. This results in a large amount of data being saved
to the log. Once the end of the heap segment is reached, a memory access
violation will occur and the server process will crash.
III. ANALYSIS
Successful exploitation of this vulnerability could allow an attacker to
crash the server process. No credentials are required. Repeated attacks
could allow the attacker to cause excessive disk space usage.
IV. DETECTION
iDefense has confirmed the existence of this vulnerability in version
8.8.1 of Novell Inc.'s eDirectory server with FTF1 applied. The
earliest version tested was 8.8. Earlier versions are suspected to be
vulnerable.
V. WORKAROUND
iDefense is unaware of any effective workaround for this issue.
VI. VENDOR RESPONSE
Novell has addressed this problem within FTF2 for eDirectory 8.8.1. More
information is available in Novell Document ID 3924657 at the following
URL.
http://www.novell.com/support/search.do?cmd=displayKC&docType=kc&externalId=3924657&sliceId=SAL_Public
VII. CVE INFORMATION
The Common Vulnerabilities and Exposures (CVE) project has assigned the
name CVE-2006-4520 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
10/21/2006 Second vendor notification
10/23/2006 Vendor response
12/06/2006 Third vendor notification
12/18/2006 Vendor response
03/21/2007 Fourth vendor notification
04/25/2007 Fifth vendor notification
04/25/2007 Vendor advised that the fix was in FTF2
04/26/2007 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 © 2007 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.
- --------------------------END INCLUDED TEXT--------------------
You have received this e-mail bulletin as a result of your organisation's
registration with AusCERT. The mailing list you are subscribed to is
maintained within your organisation, so if you do not wish to continue
receiving these bulletins you should contact your local IT manager. If
you do not know who that is, please send an email to auscert@auscert.org.au
and we will forward your request to the appropriate person.
NOTE: Third Party Rights
This security bulletin is provided as a service to AusCERT's members. As
AusCERT did not write the document quoted above, AusCERT has had no control
over its content. The decision to follow or act on information or advice
contained in this security bulletin is the responsibility of each user or
organisation, and should be considered in accordance with your organisation's
site policies and procedures. AusCERT takes no responsibility for consequences
which may arise from following or acting on information or advice contained in
this security bulletin.
NOTE: This is only the original release of the security bulletin. It may
not be updated when updates to the original are made. If downloading at
a later date, it is recommended that the bulletin is retrieved directly
from the author's website to ensure that the information is still current.
Contact information for the authors of the original document is included
in the Security Bulletin above. If you have any questions or need further
information, please contact them directly.
Previous advisories and external security bulletins can be retrieved from:
http://www.auscert.org.au/render.html?cid=1980
If you believe that your computer system has been compromised or attacked in
any way, we encourage you to let us know by completing the secure National IT
Incident Reporting Form at:
http://www.auscert.org.au/render.html?it=3192
===========================================================================
Australian Computer Emergency Response Team
The University of Queensland
Brisbane
Qld 4072
Internet Email: auscert@auscert.org.au
Facsimile: (07) 3365 7031
Telephone: (07) 3365 4417 (International: +61 7 3365 4417)
AusCERT personnel answer during Queensland business hours
which are GMT+10:00 (AEST).
On call after hours for member emergencies only.
===========================================================================
-----BEGIN PGP SIGNATURE-----
Comment: http://www.auscert.org.au/render.html?it=1967
iQCVAwUBRjFMxih9+71yA2DNAQKdvwP/Z8vUUAbnF+EJAhSpbZrbDoXvL8MuVD7h
6hRD00sjZsxgayi7ALtWdvoInLWm9sokgbhbfUQ35sAX0tCxkOZZ8oNMp7BzuuN/
zHCA97hEW860XUwim5AMvPTbA46oKGhVUkrq24HjOeoHBkHBaq5WyZXxG6PvqoMr
qYFJ03VtybI=
=Gz+l
-----END PGP SIGNATURE-----