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Date: Sun, 04 Jun 2000 21:24:00 +0200
From: Gael Duval 
Organization: MandrakeSoft
To: security-announce@linux-mandrake.com
Subject: [Security Announce] xlockmore


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   Linux-Mandrake Security Update

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Package: xlockmore

Affected versions: 6.1, 7.0

Problem: Xlock is an X11 utility used to lock X-Window displays until
the password of the user running X is entered correctly. Of course, in
order to perform the password-check xlock must be setuid root and have
access to the shadowed passwd file. In the xlockmore distributions
versions prior to 4.16.1, a buffer overflow vulnerability was present
in xlock that permitted a user to view parts of the shadowed passwd
file. This is achieved by overwriting (with an oversized -mode
argument) a global variable storing a pointer to a string printed in
the "usage" output. The pointer would be overwritten with an address
pointing to the shadowed passwd data. With the long argument, xlock
would find and an error in the command syntax and exit, printing the
usage information (along with the shadowed passwd text).

Please upgrade to:

md5sum: 614600a41689677da12287b950c2708a  
package: 6.1/RPMS/xlockmore-4.16.1-1mdk.i586.rpm

md5sum: d0a6a3bf840b4d3ea347892f8df1896e  
source: 6.1/SRPMS/xlockmore-4.16.1-1mdk.src.rpm

md5sum: 82ea685b6c467a55fce37490286763ae  
package: 7.0/RPMS/xlockmore-4.16.1-1mdk.i586.rpm

md5sum: d0a6a3bf840b4d3ea347892f8df1896e  
source: 7.0/SRPMS/xlockmore-4.16.1-1mdk.src.rpm

To upgrade automatically, use « MandrakeUpdate ». If you want to
upgrade manually, download the updated package from one of our FTP
server mirrors and uprade with "rpm -Uvh package_name". All mirrors
are listed on http://www.mandrake.com/en/ftp.php3 Updated packages are
available in the "updates/" directory.

For example, if you are looking for an updated RPM package for
Mandrake 7.0, look for it in: updates/7.0/RPMS/

Note: we give the md5 sum for each package. It lets you check the
integrity of the downloaded package by running the md5sum command on
the package ("md5sum package.rpm").