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             AUSCERT External Security Bulletin Redistribution

                    ESB-2007.0118 -- [Win][UNIX/Linux]
                         Snort: Denial of Service
                             19 February 2007

===========================================================================

        AusCERT Security Bulletin Summary
        ---------------------------------

Product:              snort versions prior to 2.6.1.2
Publisher:            Gentoo
Operating System:     UNIX variants (UNIX, Linux, OSX)
                      Windows
Impact:               Denial of Service
Access:               Remote/Unauthenticated
CVE Names:            CVE-2006-6931

Original Bulletin:    http://security.gentoo.org/glsa/glsa-200702-03.xml

Comment: This advisory references vulnerabilities in products which run on
         platforms other than Gentoo. It is recommended that administrators
         running Snort check for an updated version of the software for
         their operating system.

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Gentoo Linux Security Advisory                           GLSA 200702-03
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                                            http://security.gentoo.org/
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  Severity: Normal
     Title: Snort: Denial of Service
      Date: February 13, 2007
      Bugs: #161632
        ID: 200702-03

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Synopsis
========

Snort contains a vulnerability in the rule matching algorithm that
could result in a Denial of Service.

Background
==========

Snort is a widely deployed intrusion detection program.

Affected packages
=================

    -------------------------------------------------------------------
     Package             /  Vulnerable  /                   Unaffected
    -------------------------------------------------------------------
  1  net-analyzer/snort      < 2.6.1.2                      >= 2.6.1.2

Description
===========

Randy Smith, Christian Estan and Somesh Jha discovered that the rule
matching algorithm of Snort can be exploited in a way known as a
"backtracking attack" to perform numerous time-consuming operations.

Impact
======

A remote attacker could send specially crafted network packets, which
would result in the cessation of the detections and the consumption of
the CPU resources.

Workaround
==========

There is no known workaround at this time.

Resolution
==========

All Snort users should upgrade to the latest version:

    # emerge --sync
    # emerge --ask --oneshot --verbose ">=net-analyzer/snort-2.6.1.2"

References
==========

  [ 1 ] CVE-2006-6931
        http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2006-6931

Availability
============

This GLSA and any updates to it are available for viewing at
the Gentoo Security Website:

  http://security.gentoo.org/glsa/glsa-200702-03.xml

Concerns?
=========

Security is a primary focus of Gentoo Linux and ensuring the
confidentiality and security of our users machines is of utmost
importance to us. Any security concerns should be addressed to
security@gentoo.org or alternatively, you may file a bug at
http://bugs.gentoo.org.

License
=======

Copyright 2007 Gentoo Foundation, Inc; referenced text
belongs to its owner(s).

The contents of this document are licensed under the
Creative Commons - Attribution / Share Alike license.

http://creativecommons.org/licenses/by-sa/2.5


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