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CERT^® Advisory CA-1991-05 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.

I. Description

By default, /usr/bin/chroot is improperly installed in Ultrix versions 4.0 and 4.1.

II. Impact

System users can gain unauthorized privileges.

III. Solution

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: http://www.cert.org/advisories/CA-1991-05.html

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Revision History

September 18,1997  Attached Copyright Statement