SuSE Security Announcement: fetchmail
Aug 17, 2001, 20:09 (0 Talkback[s])
Date: Fri, 17 Aug 2001 10:25:43 +0200 (CEST)
From: Thomas Biege <thomas@suse.de>
Subject: SuSE Security Announcement: fetchmail (SuSE-SA:2001:026)
____________________________________________________________________________
SuSE Security Announcement
Package: fetchmail
Announcement-ID: SuSE-SA:2001:026
Date: Thursday, August 16th 2001 11:30 MEST
Affected SuSE versions: [6.0, 6.1, 6.2,] 6.3, 6.4, 7.0, 7.1, 7.2
Vulnerability Type: remote privilege escalation
Severity (1-10): 6
SuSE default package: yes
Other affected systems: yes
Content of this advisory:
1) security vulnerability resolved: fetchmail
problem description, discussion, solution and upgrade information
2) pending vulnerabilities, solutions, workarounds
3) standard appendix (further information)
____________________________________________________________________________
1) problem description, brief discussion, solution, upgrade information
Fetchmail is a tool for retrieving and forwarding mail. Two vulnerabilities
in the code of fetchmail were found in the last weeks.
1.) By sending a header with a large "To:" line a buffer overflow will
be triggered in the header parsing code.
2.) By impersonating a pop3 or imap server by using DNS spoofing
or getting control over the pop3/imap server an attacker could
trigger a buffer overflow in the pop3 and imap code of fetchmail.
All the attacker has to do is to fake a LIST response message and
providing two integers. One will used as index for a stack array
and the other one is the value written to this index.
Both vulnerabilities could be used to get remote access to the system with
the privilege of the user running fetchmail.
A temporary fix is not possible, so we suggest to install the new RPM
on your system.
i386 Intel Platform:
SuSE-7.2
ftp://ftp.suse.com/pub/suse/i386/update/7.2/n1/fetchmail-5.8.0-48.i386.rpm
995660f54f997eb33120c6dcdab5ca73
source rpm:
ftp://ftp.suse.com/pub/suse/i386/update/7.2/zq1/fetchmail-5.8.0-48.src.rpm
6466071439f694d89d011c35265de909
SuSE-7.1
ftp://ftp.suse.com/pub/suse/i386/update/7.1/n1/fetchmail-5.6.5-27.i386.rpm
a6185bbbd1cdeb6f4b5a7afbe8efcd31
SuSE-7.1
ftp://ftp.suse.com/pub/suse/i386/update/7.1/n2/fetchmailconf-5.6.5-0.i386.rpm
4ed63ae1652db9037c56e8a6bbf95da2
source rpm:
ftp://ftp.suse.com/pub/suse/i386/update/7.1/zq1/fetchmail-5.6.5-27.src.rpm
27aed0c7fbfb882dce9451a1c673908d
SuSE-7.0
ftp://ftp.suse.com/pub/suse/i386/update/7.0/n1/fetchml-5.4.0-3.i386.rpm
b2aec10ba865e37bef95a32f8adfa8d2
source rpm:
ftp://ftp.suse.com/pub/suse/i386/update/7.0/zq1/fetchml-5.4.0-3.src.rpm
8a133db913032e2ea04517e0d86dde5c
SuSE-6.4
ftp://ftp.suse.com/pub/suse/i386/update/6.4/n1/fetchml-5.3.0-3.i386.rpm
d8c0aed277da334a5be9d7241f2d3fc3
source rpm:
ftp://ftp.suse.com/pub/suse/i386/update/6.4/zq1/fetchml-5.3.0-3.src.rpm
732deaa4ba6e181d15c8dbabff5e309f
SuSE-6.3
ftp://ftp.suse.com/pub/suse/i386/update/6.3/n1/fetchml-5.1.2-7.i386.rpm
d0e91680594f84f161f8dfee95125e0a
source rpm:
ftp://ftp.suse.com/pub/suse/i386/update/6.3/zq1/fetchml-5.1.2-7.src.rpm
cac94bd2373d75dad6c91d66583eadfb
Sparc Platform:
SuSE-7.1
ftp://ftp.suse.com/pub/suse/sparc/update/7.1/n1/fetchmail-5.6.5-12.sparc.rpm
4d7dcbf03a030ece4dd50acd3b330ad3
source rpm:
ftp://ftp.suse.com/pub/suse/sparc/update/7.1/zq1/fetchmail-5.6.5-12.src.rpm
9d245f4358da492133e5a735497dbf2b
SuSE-7.0
ftp://ftp.suse.com/pub/suse/sparc/update/7.0/n1/fetchml-5.4.0-3.sparc.rpm
07462524836665fb3ad8da365b948f5f
source rpm:
ftp://ftp.suse.com/pub/suse/sparc/update/7.0/zq1/fetchml-5.4.0-3.src.rpm
bb2438d4e03b01415d675c2d05e3c847
AXP Alpha Platform:
SuSE-7.1
ftp://ftp.suse.com/pub/suse/axp/update/7.1/n1/fetchmail-5.6.5-16.alpha.rpm
0a4503aadd5981e9a4c2bc57a46eb9b9
source rpm:
ftp://ftp.suse.com/pub/suse/axp/update/7.1/zq1/fetchmail-5.6.5-16.src.rpm
a8c6425a9f15b04ff27a4f0636e65f93
SuSE-7.0
ftp://ftp.suse.com/pub/suse/axp/update/7.0/n1/fetchml-5.4.0-3.alpha.rpm
851a72a94dc9aa152fff3f9dfd30aeb5
source rpm:
ftp://ftp.suse.com/pub/suse/axp/update/7.0/zq1/fetchml-5.4.0-3.src.rpm
e876b48882702c6c45e01326f85a610a
SuSE-6.4
ftp://ftp.suse.com/pub/suse/axp/update/6.4/n1/fetchml-5.3.0-3.alpha.rpm
e44e632813710d4eb3b778414733631e
source rpm:
ftp://ftp.suse.com/pub/suse/axp/update/6.4/zq1/fetchml-5.3.0-3.src.rpm
27908e4fe9995dd86054533d17e85f5b
SuSE-6.3
ftp://ftp.suse.com/pub/suse/axp/update/6.3/n1/fetchml-5.1.2-4.alpha.rpm
0751d23ccdfd860409cb592b84c203e4
source rpm:
ftp://ftp.suse.com/pub/suse/axp/update/6.3/zq1/fetchml-5.1.2-4.src.rpm
ac0a757562c01bf84780fd81e04a7784
PPC PowerPC Platform:
SuSE-7.1
ftp://ftp.suse.com/pub/suse/ppc/update/7.1/n1/fetchmail-5.6.5-16.ppc.rpm
f84f2b9f669e3ba65d42ddac78b9f49c
source rpm:
ftp://ftp.suse.com/pub/suse/ppc/update/7.1/zq1/fetchmail-5.6.5-16.src.rpm
999b7fcfb1799ae98d5a2ffaf103f9a7
SuSE-7.0
ftp://ftp.suse.com/pub/suse/ppc/update/7.0/n1/fetchml-5.4.0-3.ppc.rpm
55a46529b8f9cae39cd3a3d06728e300
source rpm:
ftp://ftp.suse.com/pub/suse/ppc/update/7.0/zq1/fetchml-5.4.0-3.src.rpm
b3ecbc340fb46e5c6501f34184fa69fd
SuSE-6.4
ftp://ftp.suse.com/pub/suse/ppc/update/6.4/n1/fetchml-5.3.0-3.ppc.rpm
d3bf46ca935d696b1a45ff1b3c820840
source rpm:
ftp://ftp.suse.com/pub/suse/ppc/update/6.4/zq1/fetchml-5.3.0-3.src.rpm
6dbd73a017fd2915c9197860f47a6d28
____________________________________________________________________________
2) Pending vulnerabilities in SuSE Distributions and Workarounds:
Please watch out for upcomming announcements.
____________________________________________________________________________
3) standard appendix: authenticity verification, additional information
- Package authenticity verification:
SuSE update packages are available on many mirror ftp servers all over
the world. While this service is being considered valuable and important
to the free and open source software community, many users wish to be
sure about the origin of the package and its content before installing
the package. There are two verification methods that can be used
independently from each other to prove the authenticity of a downloaded
file or rpm package:
1) md5sums as provided in the (cryptographically signed) announcement.
2) using the internal gpg signatures of the rpm package.
1) execute the command
md5sum
after you downloaded the file from a SuSE ftp server or its mirrors.
Then, compare the resulting md5sum with the one that is listed in the
announcement. Since the announcement containing the checksums is
cryptographically signed (usually using the key security@suse.de),
the checksums show proof of the authenticity of the package.
We advise against subscribing to security lists which cause the
email message containing the announcement to be modified so that
the signature does not match after transport through the mailing
list software.
Downsides: You must be able to verify the authenticity of the
announcement in the first place. If RPM packages are being rebuilt
and a new version of a package is published on the ftp server, all
md5 sums for the files are useless.
2) rpm package signatures provide an easy way to verify the authenticity
of an rpm package. Use the command
rpm -v --checksig
to verify the signature of the package, where is the
filename of the rpm package that you have downloaded. Of course,
package authenticity verification can only target an uninstalled rpm
package file.
Prerequisites:
a) gpg is installed
b) The package is signed using a certain key. The public part of this
key must be installed by the gpg program in the directory
~/.gnupg/ under the user's home directory who performs the
signature verification (usually root). You can import the key
that is used by SuSE in rpm packages for SuSE Linux by saving
this announcement to a file ("announcement.txt") and
running the command (do "su -" to be root):
gpg --batch; gpg < announcement.txt | gpg --import
SuSE Linux distributions version 7.1 and thereafter install the
key "build@suse.de" upon installation or upgrade, provided that
the package gpg is installed. The file containing the public key
is placed at the toplevel directory of the first CD (pubring.gpg)
and at ftp://ftp.suse.com/pub/suse/pubring.gpg-build.suse.de .
- SuSE runs two security mailing lists to which any interested party may
subscribe:
suse-security@suse.com
- general/linux/SuSE security discussion.
All SuSE security announcements are sent to this list.
To subscribe, send an email to
<suse-security-subscribe@suse.com>
suse-security-announce@suse.com
- SuSE's announce-only mailing list.
Only SuSE's security annoucements are sent to this list.
To subscribe, send an email to
<suse-security-announce-subscribe@suse.com>
For general information or the frequently asked questions (faq)
send mail to:
<suse-security-info@suse.com> or
<suse-security-faq@suse.com> respectively.
===================================================
SuSE's security contact is <security@suse.com>.
The <security@suse.com> public key is listed below.
===================================================
____________________________________________________________________________
The information in this advisory may be distributed or reproduced,
provided that the advisory is not modified in any way. In particular,
it is desired that the cleartext signature shows proof of the
authenticity of the text.
SuSE GmbH makes no warranties of any kind whatsoever with respect
to the information contained in this security advisory.
Bye,
Thomas
--
Thomas Biege, SuSE GmbH, Schanzaeckerstr. 10, 90443 Nuernberg
E@mail: thomas@suse.de Function: Security Support & Auditing
"lynx -source http://www.suse.de/~thomas/contact/thomas.asc | pgp -fka"
Key fingerprint = 51 AD B9 C7 34 FC F2 54 01 4A 1C D4 66 64 09 84
