*********************************************************************** DDN Security Bulletin 9111 DCA DDN Defense Communications System 15 Aug 91 Published by: DDN Security Coordination Center (SCC@NIC.DDN.MIL) (800) 235-3155 DEFENSE DATA NETWORK SECURITY BULLETIN The DDN SECURITY BULLETIN is distributed by the DDN SCC (Security Coordination Center) under DCA contract as a means of communicating information on network and host security exposures, fixes, & concerns to security & management personnel at DDN facilities. Back issues may be obtained via FTP (or Kermit) from NIC.DDN.MIL [192.67.67.20] using login="anonymous" and password="guest". The bulletin pathname is SCC:DDN-SECURITY-yynn (where "yy" is the year the bulletin is issued and "nn" is a bulletin number, e.g. SCC:DDN-SECURITY-9001). ********************************************************************** ULTRIX LAT/Telnet Gateway Vulnerability + - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - + ! ! ! The following important advisory was issued by the Computer ! ! Emergency Response Team (CERT) and is being relayed unedited ! ! via the Defense Communications Agency's Security Coordination ! ! Center distribution system as a means of providing DDN ! ! subscribers with useful security information. ! ! ! + - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - + CA-91:11 CERT Advisory August 14, 1991 ULTRIX LAT/Telnet Gateway Vulnerability --------------------------------------------------------------------------- The Computer Emergency Response Team/Coordination Center (CERT/CC) has received information concerning a vulnerability in LAT/Telnet gateway software in Digital Equipment Corporation's (DEC) ULTRIX versions 4.1 and 4.2 on all architectures. Information regarding the exploitation of this vulnerability has been publicly disclosed so we recommend taking immediate action. Until you are able to apply the patch we recommend that sites disable the LAT/telnet service. DEC has made a patch available which consists of new /usr/ucb/telnet binaries. The patch is available through DEC's Customer Support Centers. Sites within the USA should call 1-800-525-7100. Sites in Europe and elsewhere should contact DEC through their normal channels. --------------------------------------------------------------------------- I. DESCRIPTION: A vulnerability exists such that ULTRIX 4.1 and 4.2 systems running the LAT/Telnet gateway software can allow unauthorized privileged access. Although you may not be running the LAT/Telnet service at this time, the CERT/CC urges all sites to install the patch. This will ease any future installation of the gateway software. The LAT/Telnet software requires special installation and is NOT part of the default ULTRIX configuration. II. IMPACT: Anyone who can access a terminal or modem connected to the LAT server running the LAT/Telnet service can gain unauthorized root privileges. III. SOLUTION: Obtain the appropriate version of the patch kit for your system architecture from your DEC Customer Support Center, and install according to the accompanying instructions. --------------------------------------------------------------------------- The CERT/CC would like to thank George Michaelson of The Prentice Centre, University of Queensland, Australia and John Annen of Davidson College for bringing this to our attention. We would also like to thank DEC for their response to this vulnerability and CIAC for their assistance. --------------------------------------------------------------------------- If you believe that your system has been compromised, contact CERT/CC via telephone or e-mail. Computer Emergency Response Team/Coordination Center (CERT/CC) Software Engineering Institute Carnegie Mellon University Pittsburgh, PA 15213-3890 Internet E-mail: cert@cert.sei.cmu.edu Telephone: 412-268-7090 24-hour hotline: CERT/CC personnel answer 7:30a.m.-6:00p.m. EST, on call for emergencies during other hours. Past advisories and other computer security related information are available for anonymous ftp from the cert.sei.cmu.edu (192.88.209.5) system.