NetBSD: sendmail buffer overflow vulnerabilities
Posted by LinuxSecurity.com Team   
NetBSD Fix a buffer overflow in address parsing. However, a remote exploit of the sendmail (smmsp - Sendmail MessageSubmission Program) uid could lead to opportunities to apply localexploits to further elevate privileges.

		 NetBSD Security Advisory 2003-016
		 =================================

Topic:		Sendmail - another prescan() bug CAN-2003-0694

Version:	NetBSD-current:	source prior to September 18, 2003
		NetBSD 1.6.1:	affected
		NetBSD 1.6:	affected
		NetBSD-1.5.3:	affected
		NetBSD-1.5.2:	affected
		NetBSD-1.5.1:	affected
		NetBSD-1.5:	affected
		pkgsrc:		sendmail packages prior to 8.12.10

Severity:	Remote exploit

Fixed:		NetBSD-current:		September 18, 2003
		NetBSD-1.6 branch:	September 18, 2003 (1.6.2 will include the fix)
		NetBSD-1.5 branch:	September 19, 2003
		pkgsrc:		sendmail-8.12.10 corrects this issue


Abstract
========

- From sendmail 8.12.10 release notes  (http://www.sendmail.org/8.12.10.html):

SECURITY: Fix a buffer overflow in address parsing.  Problem
	detected by Michal Zalewski, patch from Todd C. Miller
	of Courtesan Consulting.

Sendmail does not run by default on NetBSD installations.

Sendmail does not run as root when enabled on modern NetBSD installations.

However, a remote exploit of the sendmail (smmsp - Sendmail Message
Submission Program) uid could lead to opportunities to apply local
exploits to further elevate privileges.


Technical Details
=================
 
http://www.sendmail.org/8.12.10.html 
http://www.cert.org/advisories/CA-2003-25.html 
http://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2003-0694


Solutions and Workarounds
=========================

NetBSD releases since 1.5 have included the option of using the Postfix
mail system as an alternative to sendmail. For simple site
configurations, switching between sendmail and Postfix is relatively
easy, and provides a workaround to any sendmail security issues.


An upgrade of the sendmail daemon is required to address this problem.
If you have a running instance of sendmail on your system, it must
be restarted once the installed binary is updated.

The following version string identifies a patched version; if you have
one of these versions, your system is already safe.

	NetBSD-current: 8.12.9p1
	NetBSD-1.6.x: 8.11.6p3
	NetBSD-1.5.x: 8.11.6p3

The following instructions describe how to upgrade your sendmail
binaries by updating your source tree and rebuilding and
installing a new version of sendmail.

* NetBSD-current:

	Systems running NetBSD-current dated from before 2003-09-17
	should be upgraded to NetBSD-current dated 2003-09-18 or later.

	The following directories need to be updated from the
	netbsd-current CVS branch (aka HEAD):
		src/gnu/dist/sendmail/sendmail/parseaddr.c

	To update from CVS, re-build, and re-install sendmail:

		# cd src
		# cvs update -d -P gnu/dist/sendmail/sendmail/parseaddr.c
		# cd gnu/usr.sbin/sendmail

		# make USETOOLS=no cleandir dependall
		# make USETOOLS=no install


* NetBSD 1.6, 1.6.1:

	The binary distribution of NetBSD 1.6 and 1.6.1 are vulnerable.

	Systems running NetBSD 1.6 sources dated from before
	2003-09-17 should be upgraded from NetBSD 1.6 sources dated
	2003-09-18 or later.

	NetBSD 1.6.2 will include the fix.

	The following directories need to be updated from the
	netbsd-1-6 CVS branch:
		src/gnu/dist/sendmail/sendmail/parseaddr.c

	To update from CVS, re-build, and re-install sendmail:

		# cd src
		# cvs update -d -P -r netbsd-1-6 \
			gnu/dist/sendmail/sendmail/parseaddr.c
		# cd gnu/usr.sbin/sendmail

		# make USETOOLS=no cleandir dependall
		# make USETOOLS=no install


* NetBSD 1.5, 1.5.1, 1.5.2, 1.5.3:

	The binary distribution of NetBSD 1.5 to 1.5.3 are vulnerable.   

	Systems running NetBSD 1.5, 1.5.1, 1.5.2, or 1.5.3 sources dated
	from before 2003-09-18 should be upgraded from NetBSD 1.5.*
	sources dated 2003-09-19 or later.

	The following directories need to be updated from the
	netbsd-1-5 CVS branch:
		src/gnu/dist/sendmail/sendmail/parseaddr.c

	To update from CVS, re-build, and re-install sendmail:

		# cd src
		# cvs update -d -P -r netbsd-1-5 \
			gnu/dist/sendmail/sendmail/parseaddr.c
		# cd gnu/usr.sbin/sendmail

		# make cleandir dependall
		# make install


Thanks To
=========

Andrew Brown, and CERT


Revision History
================

	2003-10-09	Initial release


More Information
================

Advisories may be updated as new information becomes available.
The most recent version of this advisory (PGP signed) can be found at  
ftp://ftp.NetBSD.org/pub/NetBSD/security/advisories/NetBSD-SA2003-016.txt.asc

Information about NetBSD and NetBSD security can be found at 
http://www.NetBSD.org/ and  http://www.NetBSD.org/Security/.


Copyright 2003, The NetBSD Foundation, Inc.  All Rights Reserved.
Redistribution permitted only in full, unmodified form.

$NetBSD: NetBSD-SA2003-016.txt,v 1.5 2003/10/09 17:49:45 david Exp $