*********************************************************************** DDN Security Bulletin 9109 DCA DDN Defense Communications System 23 July 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). ********************************************************************** Patch for SunOS /usr/etc/rpc.mountd + - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - + ! ! ! 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-91:09 CERT Advisory July 15, 1991 Patch for SunOS /usr/etc/rpc.mountd --------------------------------------------------------------------------- The Computer Emergency Response Team/Coordination Center (CERT/CC) has received information concerning the availability of a security patch for /usr/etc/rpc.mountd in Sun Microsystems, Inc. operating systems. This problem will be fixed in SunOS 5.0. Patches are available for SunOS 4.1, and SunOS 4.1.1 through your local Sun answer centers worldwide as well as through anonymous ftp to ftp.uu.net (in ~ftp/sun-dist). Patch ID and file information are as follows: Fix Patch ID Filename Checksum /usr/etc/rpc.mountd 100296-01 100296-01.tar.Z 01501 233 Please note that Sun Microsystems sometimes updates patch files. If you find that the checksum is different please contact Sun Microsystems or us for verification. --------------------------------------------------------------------------- I. DESCRIPTION: If an access list of hosts within /etc/exports is a string over 256 characters then the filesystem can be mounted by everyone. II. IMPACT: Unauthorized remote hosts will be able to mount the filesystem. III. SOLUTION: As root: 1. Move the existing rpc.mountd aside # mv /usr/etc/rpc.mountd /usr/etc/rpc.mountd.OLD 2. Install the new version # cp sun{3,3x,4,4c}/{4.1,4.1.1,4.1_PSR_A}/rpc.mountd /usr/etc # chown root.staff /usr/etc/rpc.mountd # chmod 755 /usr/etc/rpc.mountd 3. Kill the currently running rpc.mountd and restart it, or, reboot the system. Systems currently mounting filesystems from this host will have interruptions in service either way. --------------------------------------------------------------------------- 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.