DEC Ultrix Vulnerability
Original issue date: May 1, 1991
Last revised: September 18, 1997
Attached copyright statement
A complete revision history is at the end of this file.
The Computer Emergency Response Team/Coordination Center (CERT/CC) has
received information concerning a vulnerability in Digital Equipment
Corporation's (DEC) Ultrix operating system versions 4.0 and 4.1 for all
DEC architectures. The vulnerability has been fixed in version 4.2 which
will be shipped beginning in late May. DEC has also provided a suggested
fix for versions 4.0 and 4.1.
By default, /usr/bin/chroot is improperly installed in Ultrix
versions 4.0 and 4.1.
System users can gain unauthorized privileges.
Change the permission on the file /usr/bin/chroot.
# chmod 700 /usr/bin/chroot
Our thanks to Eric R. Jorgensen and Brian Ellis of UnixOps / Distributed
Computing Services at the University of Colorado, Boulder, for bringing this
problem to our attention. The CERT/CC would also like to thank Digital for
their response to this vulnerability.
This document is available from:
CERT/CC Contact Information
Phone: +1 412-268-7090 (24-hour hotline)
Fax: +1 412-268-6989
CERT Coordination Center
Software Engineering Institute
Carnegie Mellon University
Pittsburgh PA 15213-3890
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Getting security information
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Copyright 1991 Carnegie Mellon University.
September 18,1997 Attached Copyright Statement