[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
CSIRTUK ADVISORY - 3477 - Novell - NetWare Client Local Privilege Escalation Vulnerability
CSIRTUK ADVISORY - 3477 dated 15.11.07 time 13:18
Centre for the Protection of National Infrastructure (CPNI)
Further details about CPNI, including information about our products
found at www.cpni.gov.uk
Please note that CSIRTUK RSS Feeds are available from:
Novell NetWare Client Local Privilege Escalation Vulnerability
Date: 15 November 2007 13:18
Title: 3477 - Novell NetWare Client Local Privilege Escalation
Abstract: Local exploitation of an input validation error vulnerability
within Novell NetWare Client could allow an unprivileged attacker to
execute arbitrary code within the kernel.
Operating Systems affected: Netware
Applications affected:NetWare Client
Advisory type: Information
Adversity source: Unknown
Attack Vector: Vulnerability exploitation
Warning Status: Information only
Potential Damage: Remote unauthorised access
Possible Duration: Unknown
Availability of fix: Available
Type of fix: Patch
Source: iDefense, Inc.
Reliability of source: Known
iDefense Security Advisory 11.12.07
Nov 12, 2007
The Novell Client software provides a workstation with access to Novell
NetWare networks as well as Novell Open Enterprise Server (OES)
services. Novell Clients can access the full range of Novell services
such as authentication via Novell eDirectory, network browsing and
service resolution, and secure and reliable file system access. More
information about the Novel Client can be found on the vendor's site at
the following URL.
Local exploitation of an input validation error vulnerability within
Novell NetWare Client could allow an unprivileged attacker to execute
arbitrary code within the kernel.
When the Novell NetWare Client is installed on a Windows based operating
system, the driver nwfilter.sys will be loaded at system startup. This
driver allows any user to open the device "\.\nwfilter" and issue IOCTLs
with a buffering mode of METHOD_NEITHER.
The problem specifically exists because the driver allows untrusted user
mode code to pass kernel addresses as arguments to the driver. With
specially constructed input, a malicious user can use functionality
within the driver to patch kernel addresses and execute arbitrary code
within kernel mode.
Exploitation of this vulnerability allows an unprivileged local user to
patch and execute arbitrary code within the kernel. In order to exploit
the vulnerability, an attacker needs to be able to log in to the target
machine and execute a specially crafted executable.
iDefense has confirmed the existence of this vulnerability in
nwfilter.sys, file version 188.8.131.52, as included with Novell's NetWare
Client 4.91 SP4. Other versions are suspected vulnerable as well.
iDefense is currently unaware of any workaround for this issue.
VI. VENDOR RESPONSE
Novell has addressed this vulnerability by releasing patches that remove
the "nwfilter.sys" driver. For more information, consult Novell's
advisory at the following URL.
VII. CVE INFORMATION
The Common Vulnerabilities and Exposures (CVE) project has assigned the
name CVE-2007-5667 to this issue. This is a candidate for inclusion in
the CVE list (http://cve.mitre.org/), which standardizes names for
VIII. DISCLOSURE TIMELINE
09/25/2007 Initial vendor notification
09/25/2007 Initial vendor response
11/12/2007 Coordinated public disclosure
This vulnerability was reported to iDefense by Stephen Fewer of Harmony
Get paid for vulnerability research
Free tools, research and upcoming events http://labs.idefense.com/
X. LEGAL NOTICES
Copyright (c) 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@xxxxxxxxxxxx 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,
CPNI values your feedback.
1. Which of the following most reflects the value of the advisory to
(Place an 'X' next to your choice)
Very useful:__ Useful:__ Not useful:__
2. If you did not find it useful, why not?
3. Any other comments? How could we improve our advisories?
Thank you for your contribution.
CSIRTUK wishes to acknowledge the contributions of iDefense and Novell
for the information contained in this advisory.
This advisory contains information released by the original author. Some
information may have changed since it was released. If the issue affects
it may be prudent to retrieve the advisory from the site of the original
source to ensure that you receive the most current information
Reference to any specific commercial product, process, or service by
name, trademark manufacturer, or otherwise, does not constitute or imply
endorsement, recommendation, or favouring by CPNI. The views and
authors expressed within this notice shall not be used for advertising
product endorsement purposes.
CPNI shall not accept responsibility for any errors or omissions
within this advisory. In particular, they shall not be liable for any
damage whatsoever, arising from or in connection with the usage of
contained within this advisory.
CSIRTUK is a member of the Forum of Incident Response and Security Teams
and has contacts with other international Incident Response Teams (IRTs)
order to foster cooperation and coordination in incident prevention, to
rapid reaction to incidents, and to promote information sharing amongst
members and the community at large.
<End of CPNI Advisory>
The original of this email was scanned for viruses by the Government Secure Intranet Anti-Virus service supplied by Cable&Wireless in partnership with MessageLabs. (CCTM Certificate Number 2006/04/0007.) On leaving the GSi this email was certified virus free.
Communications via the GSi may be automatically logged, monitored and/or recorded for legal purposes.