-----BEGIN PGP SIGNED MESSAGE----- __________________________________________________________ The U.S. Department of Energy Computer Incident Advisory Capability ___ __ __ _ ___ / | /_\ / \___ __|__ / \ \___ __________________________________________________________ INFORMATION BULLETIN Vulnerability in IRIX csetup January 9, 1997 18:00 GMT Number H-20 ______________________________________________________________________________ PROBLEM: A vulnerability in the csetup program. PLATFORM: IRIX 5.x, 6.0, 6.01, 6.1, and 6.2 DAMAGE: May allow local users to gain root privileges. SOLUTION: Until patches are available, sites are recommended to take the action suggested in Section III. ______________________________________________________________________________ VULNERABILITY Exploit details involving this vulnerability have been made ASSESSMENT: publicly available. ______________________________________________________________________________ [ Start CERT Advisory ] ============================================================================= CERT(sm) Advisory CA-97.03 Original issue date: January 8, 1997 Last revised: -- Topic: Vulnerability in IRIX csetup - - ----------------------------------------------------------------------------- The CERT Coordination Center has received information about a vulnerability in the csetup program under IRIX versions 5.x, 6.0, 6.0.1, 6.1, and 6.2. csetup is not available under IRIX 6.3 and 6.4. By exploiting this vulnerability, local users can create or overwrite arbitrary files on the system. With this leverage, they can ultimately gain root privileges. Exploitation information involving this vulnerability has been made publicly available. We recommend applying a vendor patch when possible. In the meantime, we urge sites to apply the workaround described in Section III. We will update this advisory as we receive additional information. Please check advisory files regularly for updates that relate to your site. Note: Development of this advisory was a joint effort of the CERT Coordination Center and AUSCERT. - - ----------------------------------------------------------------------------- I. Description There is a vulnerability in the csetup program under IRIX versions 5.x, 6.0, 6.0.1, 6.1, and 6.2. csetup is not available under IRIX 6.3 and 6.4. csetup is part of the Desktop System Administration subsystem. The program provides a graphical interface allowing privileged users, as flagged in the objectserver (cpeople (1M)), or root to modify system and network configuration parameters. The csetup program is setuid root to allow those who are flagged as privileged users to modify system critical files. It is possible to configure csetup to run in DEBUG mode, creating a logfile in a publicly writable directory. This file is created in an insecure manner; and because csetup is running with root privileges at the time the logfile is created, it is possible for local users to create or overwrite arbitrary files on the system. Exploit information involving this vulnerability has been made publicly available. II. Impact Anyone with access to an account on the system can create or overwrite arbitrary files on the system. With this leverage, they can ultimately gain root privileges. III. Solution Currently there are no vendor patches available that address this vulnerability. We recommend installing official vendor patches when they are made available. If the /usr/Cadmin/bin/csetup file is installed setuid root at your site, the following workaround is recommended until vendor patches are available. Sites can prevent the exploitation of this vulnerability by immediately removing the setuid privileges on csetup. # /bin/chmod 0700 /usr/Cadmin/bin/csetup # /bin/ls -l /usr/Cadmin/bin/csetup -rwx------ 1 root sys 363360 Aug 20 12:10 /usr/Cadmin/bin/csetup Next, the file /var/tmp/csetupLog should be created with permissions 0600. The sticky bit should also be set on /var/tmp/ (this is a good security practice in general). # /bin/chmod 1777 /var/tmp # /bin/touch /var/tmp/csetupLog # /bin/chmod 0600 /var/tmp/csetupLog (Note that the /var/tmp directory is not cleared at boot time.) Before executing the csetup program, the root user should confirm the existence, ownership, and the access permissions of /var/tmp/csetupLog. Ensure that csetupLog is not linked to any other file. The impact of this workaround is that only the root user will be able to use this program for its intended purpose. Privileged users previously established using the /usr/Cadmin/bin/cpeople program will no longer be able to do the system administration tasks they were previously able perform using the csetup program. - - ----------------------------------------------------------------------------- This advisory is a collaborative effort between AUSCERT and the CERT Coordination Center. The CERT Coordination Center acknowledges Yuri Volobuev for reporting the original problem, and Silicon Graphics, Inc. for their strong support in the development of the advisory. - - ----------------------------------------------------------------------------- [ End CERT Advisory ] _______________________________________________________________________________ CIAC wishes to acknowledge the contributions of AUSCERT & CERT 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: +1 510-422-8193 FAX: +1 510-423-8002 STU-III: +1 510-423-2604 E-mail: ciac@llnl.gov For emergencies and off-hour assistance, DOE, DOE contractor sites, and the NIH may contact CIAC 24-hours a day. During off hours (5PM - 8AM PST), call the CIAC voice number 510-422-8193 and leave a message, or call 800-759-7243 (800-SKY-PAGE) to send a Sky Page. CIAC has two Sky Page PIN numbers, the primary PIN number, 8550070, is for the CIAC duty person, and the secondary PIN number, 8550074 is for the CIAC Project Leader. Previous CIAC notices, anti-virus software, and other information are available from the CIAC Computer Security Archive. World Wide Web: http://ciac.llnl.gov/ Anonymous FTP: ciac.llnl.gov (128.115.19.53) Modem access: +1 (510) 423-4753 (28.8K baud) +1 (510) 423-3331 (28.8K baud) CIAC has several self-subscribing mailing lists for electronic publications: 1. CIAC-BULLETIN for Advisories, highest priority - time critical information and Bulletins, important computer security information; 2. CIAC-NOTES for Notes, a collection of computer security articles; 3. SPI-ANNOUNCE for official news about Security Profile Inspector (SPI) software updates, new features, distribution and availability; 4. SPI-NOTES, for discussion of problems and solutions regarding the use of SPI products. Our mailing lists are managed by a public domain software package called ListProcessor, which ignores E-mail header subject lines. To subscribe (add yourself) to one of our mailing lists, send the following request as the E-mail message body, substituting CIAC-BULLETIN, CIAC-NOTES, SPI-ANNOUNCE or SPI-NOTES for list-name and valid information for LastName FirstName and PhoneNumber when sending E-mail to ciac-listproc@llnl.gov: subscribe list-name LastName, FirstName PhoneNumber e.g., subscribe ciac-notes OHara, Scarlett W. 404-555-1212 x36 You will receive an acknowledgment containing address, initial PIN, and information on how to change either of them, cancel your subscription, or get help. 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. LAST 10 CIAC BULLETINS ISSUED (Previous bulletins available from CIAC) H-11: sendmail Group Permissions Vulnerability H-12: IBM AIX(r) 'SYN Flood' and 'Ping o' Death' Vulnerabilities H-13: IBM AIX(r) Security Vulnerabilities (gethostbyname, lquerypv) H-14: SGI IRIX Vulnerabilities (systour, OutOfBox, cdplayer, datman) H-15: Korn Shell (ksh) suid_exec Vulnerability H-16: HP-UX Security Vulnerabilities (chfn, Remote Watch) H-06a: Sun libc/libnsl vulnerabilities (Sun Bulletin #00137a) H-17: cron/crontab Buffer Overrun Vulnerabilities H-18: Denial-of-Service Attack via ping H-19: HP Software Installation Programs Vulnerability RECENT CIAC NOTES ISSUED (Previous Notes available from CIAC) Notes 07 - 3/29/95 A comprehensive review of SATAN Notes 08 - 4/4/95 A Courtney update Notes 09 - 4/24/95 More on the "Good Times" virus urban legend Notes 10 - 6/16/95 PKZ300B Trojan, Logdaemon/FreeBSD, vulnerability in S/Key, EBOLA Virus Hoax, and Caibua Virus Notes 11 - 7/31/95 Virus Update, Hats Off to Administrators, America On-Line Virus Scare, SPI 3.2.2 Released, The Die_Hard Virus Notes 12 - 9/12/95 Securely configuring Public Telnet Services, X Windows, beta release of Merlin, Microsoft Word Macro Viruses, Allegations of Inappropriate Data Collection in Win95 Notes 96-01 - 3/18/96 Java and JavaScript Vulnerabilities, FIRST Conference Announcement, Security and Web Search Engines, Microsoft Word Macro Virus Update -----BEGIN PGP SIGNATURE----- Version: 2.6.2 iQCVAwUBMxtcVLnzJzdsy3QZAQHIJAP/X1GGiURZeiBAgK24BFBsiWvRB9I9zA7Y 8zSY2ACbBsqleMpXNAYVFbvkvSh963JHZR16zkcKZvnvMfj4B1+ahbeCF+TRA4aF vG+P2yszkX7dkBY5f6h9aEbHiRqfoGVMogMtJQTP0CTYdW60JoMZxJBX7YF+Ohk5 4dGxbPmkVJ0= =k+MH -----END PGP SIGNATURE-----