IBM AIX lspath Local File Access Vulnerability
iDEFENSE Security Advisory 02.10.05
www.idefense.com/application/poi/display?id=195&type=vulnerabilities
February 10, 2005
I. BACKGROUND
The lspath program is a setuid root application, installed by default
under newer versions of IBM AIX. It is used to display information about
MultiPath I/O devices.
II. DESCRIPTION
Local exploitation of a file access vulnerability in the lspath command
included by default in multiple versions of IBM Corp.'s AIX operating
system could allow for the reading of one line of any file on the
system, regardless of permissions.
The problem specifically exists in the -f option. If a user specifies a
file with the -f option, the first line (up to the first space) in that
file will be displayed on the screen along with an error message.
III. ANALYSIS
The format of sensitive AIX authentication files (namely
/etc/security/passwd) limit the impact of this vulnerability due to the
fact that there is no protected data on the first line of the file.
However, exploitation does not require any knowledge of application
internals, making exploitation of this vulnerability trivial, even for
unskilled attackers.
IV. DETECTION
iDEFENSE has confirmed the existence of this vulnerability in lower
patch levels of IBM AIX version 5.2. It is suspected that previous
versions are also vulnerable.
V. WORKAROUND
Only allow trusted users local access to security critical systems.
Alternately, remove the setuid bit from lspath using chmod u-s
/usr/sbin/lspath
VI. VENDOR RESPONSE
Vendor advisories for this issue are available at:
For AIX 5.2:
https://techsupport.services.ibm.com/server/pseries.subscriptionSvcs?mod
e=1&heading=AIX52&topic=SECURITY&month=ALL
For AIX 5.3:
https://techsupport.services.ibm.com/server/pseries.subscriptionSvcs?mod
e=1&heading=AIX53&topic=SECURITY&month=ALL
VII. CVE INFORMATION
A Mitre Corp. Common Vulnerabilities and Exposures (CVE) number has not
been assigned yet.
VIII. DISCLOSURE TIMELINE
12/21/2004 Initial vendor notification
01/07/2004 Initial vendor response
02/10/2004 Coordinated public disclosure
IX. CREDIT
iDEFENSE Labs is credited with this discovery.
Get paid for vulnerability research
http://www.idefense.com/poi/teams/vcp.jsp
X. LEGAL NOTICES
Copyright (c) 2005 iDEFENSE, Inc.
Permission is granted for the redistribution of this alert
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part of this alert in any other medium other than electronically, please
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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
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.
