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Original issue date: May 1, 1991<BR>
Last revised: September 18, 1997<BR>
Attached copyright statement

<P>A complete revision history is at the end of this file.

<P>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.

<P><HR>
<H2>I. Description</H2>

By default, /usr/bin/chroot is improperly installed in Ultrix 
versions 4.0 and 4.1.
   
<H2>II. Impact</H2>

System users can gain unauthorized privileges.

<H2>III. Solution</H2>

Change the permission on the file /usr/bin/chroot.
<PRE>
# chmod 700 /usr/bin/chroot    
</PRE>
<HR>

<P>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.

<P><HR>

<!--#include virtual="/include/footer_nocopyright.html" -->
<P>Copyright 1991 Carnegie Mellon University.</P>

<HR>

Revision History
<PRE>
September 18,1997  Attached Copyright Statement
</PRE>