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DDN Security Bulletin 90-08 DCA DDN Defense Communications System
7 May 90 Published by: DDN Security Coordination Center
(
[email protected]) (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-yy-nn (where "yy" is the year the bulletin is issued
and "nn" is a bulletin number, e.g. SCC:DDN-SECURITY-90-01).
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UNISYS U5000 /etc/passwd PROBLEM
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! !
! 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. !
! !
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CA-90-03 CERT Advisory
May 7, 1990
Unisys U5000 /etc/passwd problem
The CERT/CC has recently verified several reports of unauthorized access
to Internet connected Unisys systems. The intruder(s) gained access to
these systems by logging into vendor supplied default accounts; accounts
that had not been given passwords by the systems' owners.
Gary Garb, Corporate Computer Security Officer for Unisys Corporation,
states:
"The Unisys U5000 series UNIX systems are delivered with a number of
system logins. The logins are NOT password protected when the
customer receives the system. Unless the customer secures these logins,
the system is vulnerable to unauthorized access."
"A complete list of these logins can be found in the /etc/passwd file.
Each login is described by one record in /etc/passwd which contains a
number of fields separated by colons. The second field normally would
contain the encrypted password. The system logins will initially have
a null second field (indicated by two adjacent colons) in their descriptive
records in /etc/passwd."
"The U5000/80/85/90/95 System V Administration Guide, Volume 1 (UP13679)
begins with a chapter on "System Identification and Security". On page 1-2
it states, "All logins should have passwords ... Logins that are not needed
should be either removed (by deleting from /etc/passwd) or blocked (by
locking the login as described in the section "Locking Unused Logins" on
page 1-8). The Guide contains complete instructions on controlling logins
and passwords."
"It is the user's (system administrator's) responsibility to thoroughly
read the Guide and to ensure the security of the system. *Securing the
login entries should be of the highest priority and should be accomplished
before anyone else has access to the system.*"
The CERT/CC urges administrators of Unisys systems, as well as administrators
of systems provided by other vendors, to check their systems and insure all
accounts are protected by passwords; passwords that are different from the
default passwords provided by the vendor.
Questions regarding the security aspects of Unisys systems should be directed
to:
Gary Garb, Corporate Security Officer
Unisys Corporation
(215) 986-4038
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Dan Farmer
Computer Emergency Response Team (CERT)
Software Engineering Institute
Carnegie Mellon University
Pittsburgh, PA 15213-3890
Internet:
[email protected]
Telephone: 412-268-7090 24-hour hotline: CERT personnel answer
7:30a.m.-6:00p.m. EST, on call for
emergencies other hours.
Past advisories and other information are available for anonymous ftp
From cert.sei.cmu.edu (128.237.253.50).
Downloaded From P-80 International Information Systems 304-744-2253
