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04 October 2000

Protect yourself against future threats.


              AUSCERT External Security Bulletin Redistribution
                      ESB-2000.274 -- RHSA-2000:065-04
                 LPRng contains a critical string format bug
                               5 October 2000


	AusCERT Security Bulletin Summary

Product:                LPRng
Vendor:                 Red Hat
Operating System:       Red Hat Linux
Impact:                 Root Compromise
Access Required:        Remote

- --------------------------BEGIN INCLUDED TEXT--------------------

- ---------------------------------------------------------------------
                   Red Hat, Inc. Security Advisory

Synopsis:          LPRng contains a critical string format bug
Advisory ID:       RHSA-2000:065-04
Issue date:        2000-09-26
Updated on:        2000-10-04
Product:           Red Hat Linux
Keywords:          LPRng security lpd printing lpr syslog
Cross references:  N/A
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1. Topic:

LPRng has a string format bug in the use_syslog function which could lead
to root compromise.

2. Relevant releases/architectures:

Red Hat Linux 7.0 - i386

3. Problem description:

LPRng has a string format bug in the use_syslog function.  This function
returns user input in a string that is passed to the syslog() function as
the format string.  It is possible to corrupt the print daemon's execution
with unexpected format specifiers, thus gaining root access to the
computer.  The vulnerability is theoretically exploitable both locally and

4. Solution:

For each RPM for your particular architecture, run:

rpm -Fvh [filename]

where filename is the name of the RPM.

5. Bug IDs fixed (http://bugzilla.redhat.com/bugzilla for more info):

17756 - Critical security hole in LPRng, remote root

6. RPMs required:

Red Hat Linux 7.0:



7. Verification:

MD5 sum                           Package Name
- --------------------------------------------------------------------------
c1fc795122b067dd9549aceb75bf5694  7.0/SRPMS/LPRng-3.6.24-2.src.rpm
05251e71ae5f2d2fdbc6611eea6f8651  7.0/i386/LPRng-3.6.24-2.i386.rpm

These packages are GPG signed by Red Hat, Inc. for security.  Our key
is available at:

You can verify each package with the following command:
    rpm --checksig  <filename>

If you only wish to verify that each package has not been corrupted or
tampered with, examine only the md5sum with the following command:
    rpm --checksig --nogpg <filename>

8. References:

Originally reported to bugtraq by Chris Evans <chris@scary.beasts.org> on
25 Sep, 2000.

Copyright(c) 2000 Red Hat, Inc.

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