fetchmail-SA-2006-03.txt   [plain text]

fetchmail-SA-2006-03: crash when refusing message delivered through MDA

Topics:		fetchmail crashes when refusing a message bound for an MDA

Author:		Matthias Andree
Version:	1.0
Announced:	2007-01-04
Type:		denial of service
Impact:		fetchmail aborts prematurely
Danger:		low
Credits:	Neil Hoggarth (bug report and analysis)
CVE Name:	CVE-2006-5974
URL:		http://fetchmail.berlios.de/fetchmail-SA-2006-03.txt
Project URL:	http://fetchmail.berlios.de/

Affects:	fetchmail release = 6.3.5
		fetchmail release candidates 6.3.6-rc1, -rc2

Not affected:	fetchmail release 6.3.6

Corrected:	2006-11-14 fetchmail SVN

0. Release history

2006-11-19 -	internal review draft
2007-01-04 1.0	 ready for release

1. Background

fetchmail is a software package to retrieve mail from remote POP2, POP3,
IMAP, ETRN or ODMR servers and forward it to local SMTP, LMTP servers or
message delivery agents.

fetchmail ships with a graphical, Python/Tkinter based configuration
utility named "fetchmailconf" to help the user create configuration (run
control) files for fetchmail.

2. Problem description and Impact

Fetchmail 6.3.5 and early 6.3.6 release candidates, when delivering
messages to a message delivery agent by means of the "mda" option, can
crash (by passing a NULL pointer to ferror() and fflush()) when refusing
a message. SMTP and LMTP delivery modes aren't affected.

3. Workaround

Avoid the mda option and ship to a local SMTP or LMTP server instead.

4. Solution

Download and install fetchmail 6.3.6 or a newer stable release from
fetchmail's project site at

A. Copyright, License and Warranty

(C) Copyright 2007 by Matthias Andree, <matthias.andree@gmx.de>.
Some rights reserved.

This work is licensed under the Creative Commons
Attribution-NonCommercial-NoDerivs German License. To view a copy of
this license, visit http://creativecommons.org/licenses/by-nc-nd/2.0/de/
or send a letter to Creative Commons; 559 Nathan Abbott Way;
Stanford, California 94305; USA.

Use the information herein at your own risk.

END OF fetchmail-SA-2006-03.txt