A courier-imap update has been released for Gentoo Linux

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Gentoo Linux Security Advisory GLSA 200408-19
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http://security.gentoo.org/
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Severity: High
Title: courier-imap: Remote Format String Vulnerability
Date: August 19, 2004
Bugs: #60865
ID: 200408-19

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Synopsis
=======

There is a format string vulnerability in non-standard configurations of courier-imapd which may be exploited remotely. An attacker may be able to execute arbitrary code as the user running courier-imapd (oftentimes root).



Background
=========

Courier-IMAP is an IMAP server which is part of the Courier mail system. It provides access only to maildirs.

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

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Package / Vulnerable / Unaffected
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1 net-mail/courier-imap = 3.0.5

Description
==========

There is a format string vulnerability in the auth_debug() function which can be exploited remotely, potentially leading to arbitrary code execution as the user running the IMAP daemon (oftentimes root). A remote attacker may send username or password information containing printf() format tokens (such as "%s"), which will crash the server or cause it to execute arbitrary code.

This vulnerability can only be exploited if DEBUG_LOGIN is set to something other than 0 in the imapd config file.

Impact
=====

If DEBUG_LOGIN is enabled in the imapd configuration, a remote attacker may execute arbitrary code as the root user.

Workaround
=========

Set the DEBUG_LOGIN option in /etc/courier-imap/imapd to 0. (This is the default value.)

Resolution
=========

All courier-imap users should upgrade to the latest version:

# emerge sync

# emerge -pv ">=net-mail/courier-imap-3.0.5"
# emerge ">=net-mail/courier-imap-3.0.5"

References
=========

[ 1 ] iDEFENSE Advisory
http://www.idefense.com/application/poi/display?id=131&type=vulnerabilities&flashstatus=true

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

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

http://security.gentoo.org/glsa/glsa-200408-19.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 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/1.0