-----BEGIN PGP SIGNED MESSAGE----- [ For Public Release ] __________________________________________________________ The U.S. Department of Energy Computer Incident Advisory Capability ___ __ __ _ ___ / | /_\ / \___ __|__ / \ \___ __________________________________________________________ INFORMATION BULLETIN SGI IRIX talkd Vulnerability July 23, 1997 23:00 GMT Number H-88 ______________________________________________________________________________ PROBLEM: A vulnerability exists in the talkd communication program talk(1). PLATFORM: All SGI systems running IRIX. DAMAGE: This vulnerability may be utilized to execute commands with root privileges. SOLUTION: Apply patches or workaround listed below. ______________________________________________________________________________ VULNERABILITY Exploit details involving this vulnerability have been made ASSESSMENT: publicly available. Silicon Graphics recommends that this information be acted upon as soon as possible. ______________________________________________________________________________ [ Start SGI Advisory ] - -----BEGIN PGP SIGNED MESSAGE----- ______________________________________________________________________________ Silicon Graphics Inc. Security Advisory Title: talkd Vulnerability Number: 19970701-01-PX Date: July 23, 1997 ______________________________________________________________________________ Silicon Graphics provides this information freely to the SGI user community for its consideration, interpretation, implementation and use. Silicon Graphics recommends that this information be acted upon as soon as possible. Silicon Graphics provides the information in this Security Advisory on an "AS-IS" basis only, and disclaims all warranties with respect thereto, express, implied or otherwise, including, without limitation, any warranty of merchantability or fitness for a particular purpose. In no event shall Silicon Graphics be liable for any loss of profits, loss of business, loss of data or for any indirect, special, exemplary, incidental or consequential damages of any kind arising from your use of, failure to use or improper use of any of the instructions or information in this Security Advisory. ______________________________________________________________________________ - - ----------------------- - - --- Issue Specifics --- - - ----------------------- The talkd(8) program is a support program for the user to user communications program talk(1). As part of the start of talk communications between two users, the talkd program obtains network hostname information from DNS and then coordinates notifying users of a requested talk session. A security vulnerability has been discovered in which manipulation of provided network hostname information to the talkd program can be used to execute arbitrary commands with root privileges. Silicon Graphics Inc. has investigated the issue and recommends the following steps for neutralizing the exposure. It is HIGHLY RECOMMENDED that these measures be implemented on ALL SGI systems. This issue will be corrected in future releases of IRIX. - - -------------- - - --- Impact --- - - -------------- The talkd program (/usr/etc/talkd) is installed on all IRIX systems by default. For this particular vulnerability, a local account is not required. Furthermore, the vulnerability can be exploited remotely. This vulnerability can be utilized to execute commands with root privileges. This vulnerability has been public-ally discussed and reported in AUSCERT advisory AA-97.01 and CERT advisory CA-97.04. - - -------------------------- - - --- Temporary Solution --- - - -------------------------- Although patches are available for this issue, it is realized that there may be situations where installing the patches immediately may not be possible. The steps below can be used to remove the vulnerability by disabling the talkd program. 1) Become the root user on the system. % /bin/su - Password: # 2) Edit the file /etc/inetd.conf . Place a "#" as the first character of the talkd line to comment out and deactivate the service. # vi /usr/etc/inetd.conf {Find the following line} ntalk dgram udp wait root /usr/etc/talkd talkd {Place a "#" as the first character of the ntalk line} #ntalk dgram udp wait root /usr/etc/talkd talkd {Save the file and exit} 3) Force inetd to re-read the configuration file. # /etc/killall -HUP inetd 4) Return to previous level. # exit $ - - ---------------- - - --- Solution --- - - ---------------- OS Version Vulnerable? Patch # Other Actions ---------- ----------- ------- ------------- IRIX 3.x yes not avail Note 1 IRIX 4.x yes not avail Note 1 IRIX 5.0.x yes not avail Note 1 IRIX 5.1.x yes not avail Note 1 IRIX 5.2 yes not avail Note 1 IRIX 5.3 yes 2132 IRIX 6.0.x yes not avail Note 1 IRIX 6.1 yes not avail Note 1 IRIX 6.2 yes 2133 IRIX 6.3 yes 2133 IRIX 6.4 yes 2133 NOTES 1) upgrade operating system or see "Temporary Solution" section. Patches are available via anonymous FTP and your service/support provider. The SGI anonymous FTP site is sgigate.sgi.com (204.94.209.1) or its mirror, ftp.sgi.com. Security information and patches can be found in the ~ftp/security and ~ftp/patches directories, respectfully. ##### Patch File Checksums #### The actual patch will be a tar file containing the following files: Filename: README.patch.2132 Algorithm #1 (sum -r): 58795 8 README.patch.2132 Algorithm #2 (sum): 22126 8 README.patch.2132 MD5 checksum: 1C16F01A682CC8DB605DEC4C515B3ADD Filename: patchSG0002132 Algorithm #1 (sum -r): 39922 1 patchSG0002132 Algorithm #2 (sum): 24988 1 patchSG0002132 MD5 checksum: 1BD1683D23D164F954BEE893B3CF8B2F Filename: patchSG0002132.eoe2_sw Algorithm #1 (sum -r): 29839 26 patchSG0002132.eoe2_sw Algorithm #2 (sum): 636 26 patchSG0002132.eoe2_sw MD5 checksum: EDB8C15F7D22F7104770D591952346E7 Filename: patchSG0002132.idb Algorithm #1 (sum -r): 54227 1 patchSG0002132.idb Algorithm #2 (sum): 34895 1 patchSG0002132.idb MD5 checksum: 82E411637E20CB15E9EEFA3BA330F93D Filename: README.patch.2133 Algorithm #1 (sum -r): 53634 8 README.patch.2133 Algorithm #2 (sum): 26859 8 README.patch.2133 MD5 checksum: 20FE236BEAC79EC8614BE84B5E291841 Filename: patchSG0002133 Algorithm #1 (sum -r): 05188 1 patchSG0002133 Algorithm #2 (sum): 27188 1 patchSG0002133 MD5 checksum: A4E881E9682DA41DE8897DE71D2EE42C Filename: patchSG0002133.eoe_sw Algorithm #1 (sum -r): 24652 27 patchSG0002133.eoe_sw Algorithm #2 (sum): 6068 27 patchSG0002133.eoe_sw MD5 checksum: 7ECC472AFE5105D195BCC2B75834D666 Filename: patchSG0002133.idb Algorithm #1 (sum -r): 45369 1 patchSG0002133.idb Algorithm #2 (sum): 35211 1 patchSG0002133.idb MD5 checksum: 5BE2481FB3F325399BEE961AF0FB476C - - ------------------------ - - --- Acknowledgments --- - - ------------------------ Silicon Graphics Inc. wishes to thank the CERT Coordination Center and AUSCERT for their assistance in this issue. - - ----------------------------------------------------------- - - --- Silicon Graphics Inc. Security Information/Contacts --- - - ----------------------------------------------------------- If there are questions about this document, email can be sent to cse-security-alert@sgi.com. ------oOo------ Silicon Graphics provides security information and patches for use by the entire SGI community. This information is freely available to any person needing the information and is available via anonymous FTP and the Web. The primary SGI anonymous FTP site for security information and patches is sgigate.sgi.com (204.94.209.1). Security information and patches are located under the directories ~ftp/security and ~ftp/patches, respectively. The Silicon Graphics Security Headquarters Web page is accessible at the URL http://www.sgi.com/Support/security. For issues with the patches on the FTP sites, email can be sent to cse-security-alert@sgi.com. For assistance obtaining or working with security patches, please contact your SGI support provider. ------oOo------ Silicon Graphics provides a free security mailing list service called wiretap and encourages interested parties to self-subscribe to receive (via email) all SGI Security Advisories when they are released. Subscribing to the mailing list can be done via the Web (http://www.sgi.com/Support/security/wiretap.html) or by sending email to SGI as outlined below. % mail wiretap-request@sgi.com subscribe wiretap end ^d In the example above, is the email address that you wish the mailing list information sent to. The word end must be on a separate line to indicate the end of the body of the message. The control-d (^d) is used to indicate to the mail program that you are finished composing the mail message. ------oOo------ Silicon Graphics provides a comprehensive customer World Wide Web site. This site is located at http://www.sgi.com/Support/security. ------oOo------ For reporting *NEW* SGI security issues, email can be sent to security-alert@sgi.com or contact your SGI support provider. A support contract is not required for submitting a security report. ______________________________________________________________________________ This information is provided freely to all interested parties and may be redistributed provided that it is not altered in any way, Silicon Graphics is appropriately credited and the document retains and includes its valid PGP signature. - -----BEGIN PGP SIGNATURE----- Version: 2.6.2 iQCVAwUBM9Y9v7Q4cFApAP75AQG1PgP+OV1lJX8FOpH2Np6dF8GBymnB6EemhDex O4R1m1TxjuBapWNTjIFcdCHKygnto/9Mq0oAmS7LoHfEz3+LZN/d/2uJwTJRvlV+ ttSgiVNIbP+jyiiVnhSV7U+IWtUNBBqgDCfQIxRjgmWnuIr9BjVRQfC4szDXQkXd 5PApltoJERo= =o3DO - -----END PGP SIGNATURE----- - -+#+--+#+--+#+--+#+--+#+--+#+--+#+--+#+--+#+--+#+--+#+--+#+--+#+--+#+--+ This message was posted through the FIRST mailing list server. if you wish to unsubscribe from this mailing list, send the message body of "unsubscribe first-teams" to first-majordomo@FIRST.ORG - -+#+--+#+--+#+--+#+--+#+--+#+--+#+--+#+--+#+--+#+--+#+--+#+--+#+--+#+--+ [ End SGI Advisory ] ______________________________________________________________________________ CIAC wishes to acknowledge the contributions of Silicon Graphics Inc. 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 (198.128.39.53) 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 Majordomo, 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: E-mail to ciac-listproc@llnl.gov or majordomo@tholia.llnl.gov: subscribe list-name e.g., subscribe ciac-notes You will receive an acknowledgment email immediately with a confirmation that you will need to mail back to the addresses above, as per the instructions in the email. This is a partial protection to make sure you are really the one who asked to be signed up for the list in question. If you include the word 'help' in the body of an email to the above address, it will also send back an information file on how to subscribe/unsubscribe, get past issues of CIAC bulletins via email, etc. 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-79: Vellum 3D CD-ROM contains Mac MBDF Virus H-80: SGI IRIX xlock Vulnerability H-42a: HP MPE/iX with ICMP Echo Request (ping) Vulnerability H-81: HP-UX swinstall command in SD-UX Vulnerability H-82: Lynx Temporary Files & Downloading Vulnerabilities H-83: Solaris ping Vulnerability H-84: Windows NT NtOpenProcessToken Vulnerability H-85: INN News Server Vulnerabilities H-86: ld.so Vulnerability H-87: HP-UX rlogin Vulnerability -----BEGIN PGP SIGNATURE----- Version: 4.0 Business Edition iQCVAwUBM9e12LnzJzdsy3QZAQEWzAP/bBZUEjjOIBfm+lMbj40IYhZ4d/zHS4Ku QSMOhJgtnJ3fOWxLcHCw2r+T8WwbLjE36hjwdRmBOLLfJ9SFtkGP6etUikEHRWGd MXPi3gl/ay4c61bya2Bx9SpAUmjMC1UglujU2zpcS9D53DKPecM1iBiw++QELyXG sWafKPTAB+c= =XA1p -----END PGP SIGNATURE-----