CERT® Advisory CA-1991-05 DEC Ultrix VulnerabilityOriginal 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.
I. DescriptionBy default, /usr/bin/chroot is improperly installed in Ultrix versions 4.0 and 4.1.
II. ImpactSystem users can gain unauthorized privileges.
III. SolutionChange 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: http://www.cert.org/advisories/CA-1991-05.html
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Copyright 1991 Carnegie Mellon University.
September 18,1997 Attached Copyright Statement