From labs-no-reply@idefense.com Thu Apr 7 13:49:40 2005 From: iDEFENSE Labs To: bugtraq@securityfocus.com, vulnwatch@vulnwatch.org Date: Thu, 7 Apr 2005 13:06:54 -0400 Subject: iDEFENSE Security Advisory 04.07.05: SGI IRIX gr_osview Information Disclosure Vulnerability SGI IRIX gr_osview Information Disclosure Vulnerability iDEFENSE Security Advisory 04.07.05 http://www.idefense.com/application/poi/display?type=vulnerabilities April 7, 2005 I. BACKGROUND The gr_osview application is a setuid root application that provides a graphical display of usage of certain types of operating system resources. It is installed by default under multiple versions of IRIX 6. II. DESCRIPTION Local exploitation of an information disclosure vulnerability in the gr_osview command included in multiple versions of Silicon Graphics Inc.'s IRIX Operating System could allow for the disclosure of sensitive information such as the root user's password hash. The vulnerability specifically exists in the way that gr_osview opens user-specified description files without dropping privileges. When this is combined with the debug option, it is possible to dump a line from an arbitrary file, regardless of its protection. An example is as follows: user@irix$ gr_osview -d -D /etc/shadow sgets: waiting for string *SR> read gr_osview: description file format error on line 1 To elevate privileges, the attacker would then have to crack the root password using the acquired hash. III. ANALYSIS All that is required to exploit this vulnerability is a local account and an open X display, which could be the attacker's home machine or another compromised computer. Exploitation does not require any knowledge of application internals, making exploitation trivial, even for unskilled attackers. The most effective exploitation method would be reading the first line of the operating system shadow file and then attempting to crack the root password hash. If successful, this would lead to a full root compromise. IV. DETECTION iDEFENSE has confirmed the existence of this vulnerability in SGI IRIX version 6.5.22 (maintenance). It is suspected that previous and later versions of both the feature and maintenance revisions of IRIX 6.5 are also vulnerable. V. WORKAROUND Only allow trusted users local access to security-critical systems. 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 930892. Related security advisories are available at: http://www.sgi.com/support/security/advisories.html Related patches are available at: http://www.sgi.com/support/security/patches.html ftp://patches.sgi.com/support/free/security/patches/ VII. CVE INFORMATION The Common Vulnerabilities and Exposures (CVE) project has assigned the names CAN-2005-0464 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 Free tools, research and upcoming events 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 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.