A libpng security update has been released for Gentoo Linux

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Gentoo Linux Security Advisory GLSA 200405-06
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http://security.gentoo.org/
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Severity: Normal
Title: libpng denial of service vulnerability
Date: May 14, 2004
Bugs: #49887
ID: 200405-06

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Synopsis
=======

A bug in the libpng library can be abused to crash programs making use of that library to decode PNG images.



Background
=========

libpng is a standard library used to process PNG (Portable Network Graphics) images.

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

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Package / Vulnerable / Unaffected
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1 media-libs/libpng = 1.2.5-r5

Description
==========

libpng provides two functions (png_chunk_error and png_chunk_warning) for default error and warning messages handling. These functions do not perform proper bounds checking on the provided message, which is limited to 64 bytes. Programs linked against this library may crash when handling a malicious PNG image.

Impact
=====

This vulnerability could be used to crash various programs using the libpng library, potentially resulting in a denial of service attack on vulnerable daemon processes.

Workaround
=========

There is no known workaround at this time. All users are advised to upgrade to the latest available version of libpng.

Resolution
=========

All users of libpng should upgrade to the latest stable version:

# emerge sync

# emerge -pv ">=media-libs/libpng-1.2.5-r5"
# emerge ">=media-libs/libpng-1.2.5-r5"

You should also run revdep-rebuild to rebuild any packages that depend on older versions of libpng :

# revdep-rebuild

References
=========

[ 1 ] CAN-2004-0421
http://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2004-0421

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

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

http://security.gentoo.org/glsa/glsa-200405-06.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 security@gentoo.org or alternatively, you may file a bug at http://bugs.gentoo.org.

License
======

Copyright 2004 Gentoo Technologies, 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/1.0