__________________________________________________________ The U.S. Department of Energy Computer Incident Advisory Capability ___ __ __ _ ___ / | /_\ / \___ __|__ / \ \___ __________________________________________________________ INFORMATION BULLETIN Sun Solaris dtsession Security Vulnerability [Sun(sm) Alert Notification 53288] April 4, 2003 19:00 GMT Number N-072 ______________________________________________________________________________ PROBLEM: A heap buffer overflow exists in dtsession. PLATFORM: * Sun Solaris 2.5.1 * Sun Solaris 2.6 * Sun Solaris 7 * Sun Solaris 8 * Sun Solaris 9 DAMAGE: A valid length check has not been implemented when handling the HOME variable. By carefully crafting data, a local user could cause a heap buffer overflow and execute arbitrary code with root privileges. SOLUTION: Apply patch or workaround as stated in Sun's Alert notification. ______________________________________________________________________________ VULNERABILITY The risk is MEDIUM. The dtsession(1)CDE Session Manager runs ASSESSMENT: with root privileges. In order to exploit this vulnerability, an attacker would need a legitimate account and permission on the target system. ______________________________________________________________________________ LINKS: CIAC BULLETIN: http://www.ciac.org/ciac/bulletins/n-072.shtml ORIGINAL BULLETIN: http://www.sunsolve.sun.com/pub-cgi/ retrieve.pl?doc=fsalert%2F52388&zone_32=category%3Asecurity ______________________________________________________________________________ [***** Start Sun(sm) Alert Notification 53288 *****] Sun(sm) Alert Notification Sun Alert ID: 52388 Synopsis: Security Vulnerability with /usr/dt/bin/dtsession Category: Security Product: Solaris, CDE BugIDs: 4788212 Avoidance: Workaround State: Committed Date Released: 03-Apr-2003 Date Closed: Date Modified: 1. Impact A local user may be able to execute arbitrary code or commands with the privileges of the dtsession(1) CDE Session Manager. The dtsession(1) CDE Session Manager runs with root privileges. This issue is described in NSFOCUS Security Bulletin SA2003-03 available from http://www.nsfocus.com/english/homepage/sa2003-03.htm . Sun acknowledges with thanks, NSFOCUS Information Technology, for bringing this issue to our attention. 2. Contributing Factors This issue can occur in the following releases: SPARC Platform Solaris 2.6 Solaris 7 Solaris 8 Solaris 9 without patch 114497-01 x86 Platform Solaris 2.6 Solaris 7 Solaris 8 Solaris 9 without patch 114498-01 Note: Solaris 2.5.1 will not be evaluated regarding the potential impact of the issue described in this Sun Alert document. 3. Symptoms There are no predictable symptoms that show this issue has been exploited. Solution Summary Top 4. Relief/Workaround To work around the described issue, turn off the set-user-ID ("setuid") bit for dtsession as root, shown below: # chmod 0555 /usr/dt/bin/dtsession This will cause dtsession to not be able to unlock the screen by the list of keyholders (including root), see dtsession(1) for further information. Furthermore, this will cause locally defined users in /etc/passwd to not be able to unlock the screen. NIS/NIS+ users will be able to continue to unlock the screen. Thus caution should be used for local users. For these users once the set-user-ID bit has been turned off they should use xlock(1) and turn off automatic locking by dtsession. Auto locking can be turned off by using dtstyle manager's ("dtstyle") screen option. Once the screen option popup appears, turn off auto locking by selecting the "off" choice for the Screen Saver and Screen Lock options. Then in order to lock the screen the user will need to use "xlock" from the command line of a terminal window. Note: Dates for patch availability for Solaris 2.6, 7, and 8 are not yet determined. This Sun Alert will be updated when more information or patches become available. 5. Resolution This issue is addressed in the following releases: SPARC Platform Solaris 9 with patch 114497-01 or later x86 Platform Solaris 9 with patch 114498-01 or later A final resolution is pending completion. This Sun Alert notification is being provided to you on an "AS IS" basis. This Sun Alert notification may contain information provided by third parties. The issues described in this Sun Alert notification may or may not impact your system(s). Sun makes no representations, warranties, or guarantees as to the information contained herein. ANY AND ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT, ARE HEREBY DISCLAIMED. BY ACCESSING THIS DOCUMENT YOU ACKNOWLEDGE THAT SUN SHALL IN NO EVENT BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, PUNITIVE, OR CONSEQUENTIAL DAMAGES THAT ARISE OUT OF YOUR USE OR FAILURE TO USE THE INFORMATION CONTAINED HEREIN. This Sun Alert notification contains Sun proprietary and confidential information. It is being provided to you pursuant to the provisions of your agreement to purchase services from Sun, or, if you do not have such an agreement, the Sun.com Terms of Use. This Sun Alert notification may only be used for the purposes contemplated by these agreements. Copyright 2000-2003 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, CA 95054 U.S.A. All rights reserved. [***** End Sun(sm) Alert Notification 53288 *****] _______________________________________________________________________________ CIAC wishes to acknowledge the contributions of Sun Microsystems, Inc. and NSFOCUS Information Technology, CO., Ltd. for the information contained in this bulletin. _______________________________________________________________________________ CIAC, the Computer Incident Advisory Capability, is the computer security incident response team for the U.S. Department of Energy (DOE) and the emergency backup response team for the National Institutes of Health (NIH). CIAC is located at the Lawrence Livermore National Laboratory in Livermore, California. CIAC is also a founding member of FIRST, the Forum of Incident Response and Security Teams, a global organization established to foster cooperation and coordination among computer security teams worldwide. CIAC services are available to DOE, DOE contractors, and the NIH. CIAC can be contacted at: Voice: +1 925-422-8193 (7x24) FAX: +1 925-423-8002 STU-III: +1 925-423-2604 E-mail: ciac@ciac.org Previous CIAC notices, anti-virus software, and other information are available from the CIAC Computer Security Archive. World Wide Web: http://www.ciac.org/ Anonymous FTP: ftp.ciac.org PLEASE NOTE: Many users outside of the DOE, ESnet, and NIH computing communities receive CIAC bulletins. If you are not part of these communities, please contact your agency's response team to report incidents. Your agency's team will coordinate with CIAC. The Forum of Incident Response and Security Teams (FIRST) is a world-wide organization. A list of FIRST member organizations and their constituencies can be obtained via WWW at http://www.first.org/. This document was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor the University of California nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial products, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation or favoring by the United States Government or the University of California. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or the University of California, and shall not be used for advertising or product endorsement purposes. 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