CERT® Advisory CA-1989-05 DEC/Ultrix 3.0 SystemsOriginal issue date: October 17, 1989
Last revised: September 17, 1997
Attached copyright statement
A complete revision history is at the end of this file.
Recently, the CERT/CC has been working with several Unix sites that have experienced breakins. Running tftpd, accounts with guessable passwords or no passwords, and known security holes not being patched have been the bulk of the problems.
The intruder, once in, gains root access and replaces key programs with ones that create log files which contain accounts and passwords in clear text. The intruder then returns and collects the file. By using accounts which are trusted on other systems the intruder then installs replacement programs which start logging.
There have been many postings about the problem from several other net users. In addition to looking for setuid root programs in users' home directories, hidden directories '.. ' (dot dot space space), and a modified telnet program, we have received two reports from Ultrix 3.0 sites that the intruders are replacing the /usr/bin/login program. The Ultrix security hole being used in these attacks is only found in Ultrix 3.0.
Please alert CERT if you do find a problem.
This document is available from: http://www.cert.org/advisories/CA-1989-05.html
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Phone: +1 412-268-7090 (24-hour hotline)
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Copyright 1989 Carnegie Mellon University.
September 17, 1997 Attached copyright statement