Subject: iDEFENSE Security Advisory 04.07.05: SGI IRIX gr_osview File Overwrite Vulnerability
Date: Thu, 7 Apr 2005 13:06:57 -0400
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Thread-Topic: iDEFENSE Security Advisory 04.07.05: SGI IRIX gr_osview File Overwrite Vulnerability
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From: "iDEFENSE Labs" <labs-no-reply@idefense.com.>
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SGI IRIX gr_osview File Overwrite Vulnerability=20
iDEFENSE Security Advisory 04.07.05
http://www.idefense.com/application/poi/display?type=3Dvulnerabilities
April 7, 2005
I. BACKGROUND
The gr_osview application is a setuid root application that provides a=20
graphical display of usage of certain types of operating system=20
resources. It is installed by default under multiple versions of IRIX 6.
II. DESCRIPTION
Local exploitation of a file overwrite vulnerability in the gr_osview=20
command included in multiple versions of Silicon Graphics Inc.'s IRIX=20
operating system could allow for the overwriting of arbitrary files,=20
regardless of permissions.=20
The vulnerability specifically exists in the way that gr_osview opens=20
user specified files without dropping privileges. When a file is=20
specified using the "-s" option, it will be opened regardless of=20
permissions, and operating system usage information will be written into
it. An example follows:=20
user@irix$ gr_osview -s /etc/shadow=20
After execution of that command, the system shadow file will be=20
overwritten with system usage information. With a damaged shadow file,=20
users will no longer be able to log on remotely or locally.
III. ANALYSIS
All that is required to exploit this vulnerability is a local account=20
and an open X display, which could be the attacker's home machine or=20
another compromised computer. Exploitation does not require any=20
knowledge of application internals, making exploitation trivial, even=20
for unskilled attackers.
IV. DETECTION
iDEFENSE has confirmed the existence of this vulnerability in SGI IRIX=20
version 6.5.22 (maintenance). It is suspected that previous and later=20
versions of both the feature and maintenance revisions of IRIX 6.5 are=20
also vulnerable.
V. WORKAROUND
Only allow trusted users local access to security-critical systems.=20
Alternately, remove the setuid bit from inpview using:
chmod u-s /usr/sbin/gr_osview
VI. VENDOR RESPONSE
This vulnerability has been addressed in SGI BUG 930890.
Related security advisories are available at:
http://www.sgi.com/support/security/advisories.html
=20
Related patches are available at:
http://www.sgi.com/support/security/patches.htmlftp://patches.sgi.com/support/free/security/patches/
VII. CVE INFORMATION
The Common Vulnerabilities and Exposures (CVE) project has assigned the
names CAN-2005-0465 to these issues. This is a candidate for inclusion
in the CVE list (http://cve.mitre.org), which standardizes names for
security problems.
VIII. DISCLOSURE TIMELINE
02/18/2005 Initial vendor notification
02/23/2005 Initial vendor response
04/07/2005 Coordinated public disclosure
IX. CREDIT
The discoverer of this vulnerability wishes to remain anonymous.
Get paid for vulnerability research
http://www.idefense.com/poi/teams/vcp.jsp
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http://labs.idefense.com
X. LEGAL NOTICES
Copyright (c) 2005 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
email [email protected] 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.
