SUMMARY: This bulletin contains information about a vulnerability in /usr/ucb/rdist in Sun Microsystems, Inc. SunOS 4.1.1, 4.1.2, 4.1.3, and 4.1.3c on all sun3 and sun4 architectures. SunOS 4.1.3_U1, Solaris 2.x, and Solbourne's 4.1B and 4.1C are not vulnerable. This is a Sun specific bulletin. Please reference ASSIST 92-11 "/usr/ucb/rdist Vulnerability" for general information regarding other vendors. Vendor patch information is available from the ASSIST BBS in the "General Security Information" file area, and the /pub/patches directory of the ASSIST anonymous FTP system in file rdist-patch-status. See ASSIST INFORMATION RESOURCES below for BBS and FTP info. This vulnerability is being actively exploited; review ASSIST 94-02 for additional information. Patches can be obtained from local Sun Answer Centers worldwide as well as through anonymous FTP from ftp.uu.net in the /systems/sun/sun-dist directory. In Europe, these patches are available from ftp.eu.net in the /sun/fixes directory. Information concerning specific patches is detailed below. Please note that Sun sometimes updates patch files. If you find that the checksum is different, please contact Sun.
BACKGROUND: A security vulnerability exists in /usr/ucb/rdist that can be used to gain unauthorized privileges. Under some circumstances /usr/ucb/rdist can be used to create setuid root programs.
IMPACT: This vulnerability allows a local user to gain root access.
RECOMMENDED SOLUTION:
A. If rdist is not being used, change the permissions on the file
by executing the following command as root: # chmod 700 /usr/ucb/rdist
B. If rdist is being used, obtain and install the appropriate
patches according to the instructions included with the patch file.
Module Patch ID Filename
---------- --------- ---------------
rdist 100383-06 100383-06.tar.Z
BSD Checksum = 58984 121
System V Checksum = 9125 241
MD5 Checksum = f8f78ddab19af5efabb9bd66fc8f5c1a
ASSIST would like to thank the CERT Coordination Center for information contained in this bulletin.
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