BIND: Denial of Service

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Gentoo Linux Security Advisory                          
GLSA 200702-06
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                                            http://security.gentoo.or
g/
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  Severity: Normal
     Title: BIND: Denial of Service
      Date: February 17, 2007
      Bugs: #163692
        ID: 200702-06

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Synopsis
========

ISC BIND contains two vulnerabilities allowing a Denial of
Service
under certain conditions.

Background
==========

ISC BIND is the Internet Systems Consortium implementation
of the
Domain Name System (DNS) protocol.

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

   
------------------------------------------------------------
-------
     Package       /  Vulnerable  /                        
Unaffected
   
------------------------------------------------------------
-------
  1  net-dns/bind       < 9.3.4                          
    >= 9.3.4
                                                            
*>= 9.2.8

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

An unspecified improper usage of an already freed context
has been
reported. Additionally, an assertion error could be
triggered in the
DNSSEC validation of some responses to type ANY queries with
multiple
RRsets.

Impact
======

A remote attacker could crash the server through unspecified
vectors
or, if DNSSEC validation is enabled, by sending certain
crafted ANY
queries.

Workaround
==========

There is no known workaround at this time for the first
issue. The
DNSSEC validation Denial of Service can be prevented by
disabling
DNSSEC validation until the upgrade to a fixed version. Note
that
DNSSEC validation is disabled on a default configuration.

Resolution
==========

All ISC BIND 9.3 users should upgrade to the latest
version:

    # emerge --sync
    # emerge --ask --oneshot --verbose
">=net-dns/bind-9.3.4"

All ISC BIND 9.2 users should upgrade to the latest
version:

    # emerge --sync
    # emerge --ask --oneshot --verbose
">=net-dns/bind-9.2.8"

References
==========

  [ 1 ] CVE-2007-0493
        http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-200
7-0493
  [ 2 ] CVE-2007-0494
        http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE
-CVE-2007-0494

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

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

  ht
tp://security.gentoo.org/glsa/glsa-200702-06.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
securitygentoo.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