Users login

Create an account »

JOIN XATRIX

Users login

Home » Hacking News » SuSE-SA:2002:044-SuSE Security Announcement: Multiple vulnerabilities in BIND8

SuSE-SA:2002:044-SuSE Security Announcement: Multiple vulnerabilities in BIND8

by Nikola Strahija on November 15th, 2002 Content of this advisory: 1) security vulnerability resolved: Remote command execution in bind8 name server. problem description, discussion, solution and upgrade information 2) pending vulnerabilities, solutions, workarounds: BIND4, reports of trojanized tcpdump/libpcap 3) standard appendix (further information)


1) problem description, brief discussion, solution, upgrade information

The security research company ISS (Internet Security Services)
has discovered several vulnerabilities in the BIND8 name server,
including a remotely exploitable buffer overflow.

Circumstancial evidence suggests that the Internet Software
Consortium (maintainer of BIND) has been made aware of these issues
in mid-October. Distributors of Open Source operating systems,
including SuSE, were notified of these vulnerabilities via CERT
approximately 12 hours before the release of the advisories by ISS
and ISC on Tue, Nov 12. This notification did not include any details
that allowed us to identify the vulnerable code, much less prepare
a fix. Mails to ISC went unanswered for 36 hours.

The SuSE security team regrets that the Internet Software Consortium
has withheld vital information from the Internet community for so long,
putting the majority of BIND users at risk. We would like to express
our concern that the approach chosen by ISC and ISS is likely to
erode trust in the security community if it becomes a model for dealing
with security issues.

We apologize to SuSE customers for not being able to provide timely
fixes for this problem.

The advisories by ISS and ISC mention the following problems
in detail:

1. There is a buffer overflow in the way named handles
SIG records. This buffer overflow can be exploited to
obtain access to the victim host under the account
the named process is running with.

In order to exploit this problem, the attacker must
control an existing DNS domain, and must be allowed
to perform a recursive query.

The impact of this vulnerability is serious.

In all SuSE products, named is configured to run as user "named"
by default, so a potential attacker or virus/worm does not get
immediate root access. However, this is merely an additional
obstacle the attacker faces. It may be possible for the attacker
to exploit other, unpatched local vulnerabilities such as the
recently announced traceroute hole to obtain root privilege. It
may also be possible for an attacker to obtain increased privilege
by manipulating the DNS zones served by the victim BIND server.

We recommend to upgrade to the provided packages. If this is
not possible, we recommend to restrict recursive requests as a
workaround. This can be done by adding a statement such as the
following to /etc/named.conf:

options {
... existing options ...

# Restrict recursive queries to 192.168.1.*,
# except 192.168.1.254.
# Order does matter.
allow-recursion {
!192.168.1.254;
192.168.1/24;
};
};

Alternatively, you can add "recursion no;" to the options
section to turn off recursion completely.

2. There are several Denial Of Service problems in BIND8
that allow remote attackers to terminate the name server
process.

At least one of these vulnerabilities seems to be exploitable
even when the attacker is not allowed to perform recursive
queries, so that the workaround suggested above is not
effective against this bug.

Both vulnerabilities are addressed by this update, using patches
originating from ISC.

Due to the severity of this issue, we will provide update packages
for SuSE Linux 7.0, even though support for this product has officially
been discontinued.

Please download the update package for your distribution and verify its
integrity by the methods listed in section 3) of this announcement.
Then, install the packages using the command "rpm -Fhv file.rpm" to apply
the update. After updating, make sure to restart the name server
process by issuing the following command as root:

rcnamed restart

Our maintenance customers are being notified individually. The packages
are being offered to install from the maintenance web.




Intel i386 Platform:

SuSE-8.1:
ftp://ftp.suse.com/pub/suse/i386/update/8.1/rpm/i586/bind8-8.2.4-260.i586.rpm
e1c07d8c1dd74374cc37e7fa692c9de1
ftp://ftp.suse.com/pub/suse/i386/update/8.1/rpm/i586/bindutil-8.2.4-260.i586.rpm
b41734970bf88aa7b5d3debbf834b78d
ftp://ftp.suse.com/pub/suse/i386/update/8.1/rpm/i586/bind8-devel-8.2.4-260.i586.rpm
f7236e5e621725e100dbd204e2692a66
source rpm(s):
ftp://ftp.suse.com/pub/suse/i386/update/8.1/rpm/src/bind8-8.2.4-260.src.rpm
02154fbdc935a2900d70ce6a16e96543

SuSE-8.0:
ftp://ftp.suse.com/pub/suse/i386/update/8.0/n2/bind8-8.2.4-260.i386.rpm
07bc10c5c348c560084edb3c289459c9
ftp://ftp.suse.com/pub/suse/i386/update/8.0/n1/bindutil-8.2.4-260.i386.rpm
4db27e9ad4ae038d81422a0c5b9a34d0
ftp://ftp.suse.com/pub/suse/i386/update/8.0/n4/bind8-devel-8.2.4-260.i386.rpm
a1b3958e0fbaed30ddecbf7753007dbf
source rpm(s):
ftp://ftp.suse.com/pub/suse/i386/update/8.0/zq1/bind8-8.2.4-260.src.rpm
0b66ae2b5c462f041625919fed7ab089

SuSE-7.3:
ftp://ftp.suse.com/pub/suse/i386/update/7.3/n2/bind8-8.2.4-261.i386.rpm
fe0654b3de751533874b08a860afea5e
ftp://ftp.suse.com/pub/suse/i386/update/7.3/n1/bindutil-8.2.4-261.i386.rpm
043a8c1c0bb2cc23308a614dc7bdc0fe
ftp://ftp.suse.com/pub/suse/i386/update/7.3/n2/bind8-devel-8.2.4-261.i386.rpm
59aca78f5aacb3ff7ecbc252eb760956
source rpm(s):
ftp://ftp.suse.com/pub/suse/i386/update/7.3/zq1/bind8-8.2.4-261.src.rpm
355add6397435262c597ad662e3df119

SuSE-7.2:
ftp://ftp.suse.com/pub/suse/i386/update/7.2/n2/bind8-8.2.3-200.i386.rpm
1072a9fe708150bc14c70a72ca42dfd3
ftp://ftp.suse.com/pub/suse/i386/update/7.2/n1/bindutil-8.2.3-200.i386.rpm
0713d9b200db862110493233bc1d8321
ftp://ftp.suse.com/pub/suse/i386/update/7.2/n2/bind8-devel-8.2.3-200.i386.rpm
c681a91b38104cf47de4f4d454136a8a
source rpm(s):
ftp://ftp.suse.com/pub/suse/i386/update/7.2/zq1/bind8-8.2.3-200.src.rpm
8f51737bc0c84b7be08fe3bb1d4012b4

SuSE-7.1:
ftp://ftp.suse.com/pub/suse/i386/update/7.1/n2/bind8-8.2.3-200.i386.rpm
f2c14f81038d7ba952def27981b4599c
ftp://ftp.suse.com/pub/suse/i386/update/7.1/n1/bindutil-8.2.3-200.i386.rpm
961a5403a41e8031c054a081ebf92ba5
source rpm(s):
ftp://ftp.suse.com/pub/suse/i386/update/7.1/zq1/bind8-8.2.3-200.src.rpm
7f3c9b95591fb22f00dc0b22cdd5fcf1

SuSE-7.0:
ftp://ftp.suse.com/pub/suse/i386/update/7.0/n1/bind8-8.2.3-200.i386.rpm
0a6b9e23cefa5cd9f06660571ebf85ff
ftp://ftp.suse.com/pub/suse/i386/update/7.0/n1/bindutil-8.2.3-200.i386.rpm
3a6e0e81c2d8b05ee01a2a0b9c26e9a4
source rpm(s):
ftp://ftp.suse.com/pub/suse/i386/update/7.0/zq1/bind8-8.2.3-200.src.rpm
1c2cb2e531fe2834de84b22ad714de68



Sparc Platform:

SuSE-7.3:
ftp://ftp.suse.com/pub/suse/sparc/update/7.3/n2/bind8-8.2.4-128.sparc.rpm
c08454b933ed2365d9d2ab1322803af6
ftp://ftp.suse.com/pub/suse/sparc/update/7.3/n1/bindutil-8.2.4-128.sparc.rpm
47e063be85fadfa2e5d0fce1746a34b5
ftp://ftp.suse.com/pub/suse/sparc/update/7.3/n2/bind8-devel-8.2.4-128.sparc.rpm
46a97b033cca0a01dcb39ef90275ce46
source rpm(s):
ftp://ftp.suse.com/pub/suse/sparc/update/7.3/zq1/bind8-8.2.4-128.src.rpm
827a7f56273c7a25ac40ffba728e9150




AXP Alpha Platform:

SuSE-7.1:
ftp://ftp.suse.com/pub/suse/axp/update/7.1/n2/bind8-8.2.3-139.alpha.rpm
77f39990fabacb545657236a60fecbe0
ftp://ftp.suse.com/pub/suse/axp/update/7.1/n1/bindutil-8.2.3-139.alpha.rpm
33bf9f28a7c9105c84216906694c7b7c
source rpm(s):
ftp://ftp.suse.com/pub/suse/axp/update/7.1/zq1/bind8-8.2.3-139.src.rpm
df347649fc98de695837a88452814ee6

SuSE-7.0:
ftp://ftp.suse.com/pub/suse/axp/update/7.0/n1/bind8-8.2.3-139.alpha.rpm
23f307cda6a0eefb3d9f1a0439950bdd
ftp://ftp.suse.com/pub/suse/axp/update/7.0/n1/bindutil-8.2.3-139.alpha.rpm
0789b49749d93ddd79192506cda00f7a
source rpm(s):
ftp://ftp.suse.com/pub/suse/axp/update/7.0/zq1/bind8-8.2.3-139.src.rpm
356306a7f2c079e2726b3aa8da496e9b



PPC Power PC Platform:

SuSE-7.3:
ftp://ftp.suse.com/pub/suse/ppc/update/7.3/n2/bind8-8.2.4-200.ppc.rpm
4cbeb4719625f8735ec03c27e1b27b85
ftp://ftp.suse.com/pub/suse/ppc/update/7.3/n1/bindutil-8.2.4-200.ppc.rpm
37fca302d72c819e713f8038d730a527
ftp://ftp.suse.com/pub/suse/ppc/update/7.3/n2/bind8-devel-8.2.4-200.ppc.rpm
f0f5cb7b808789606448a4d472c71400
source rpm(s):
ftp://ftp.suse.com/pub/suse/ppc/update/7.3/zq1/bind8-8.2.4-200.src.rpm
5c810e6f144d0f2875bb06d2331f50d8

SuSE-7.1:
ftp://ftp.suse.com/pub/suse/ppc/update/7.1/n2/bind8-8.2.3-121.ppc.rpm
47fcc451954f03a915b57b500bd56c57
ftp://ftp.suse.com/pub/suse/ppc/update/7.1/n1/bindutil-8.2.3-121.ppc.rpm
2c0de3b64d5c3d62cb840a534911ef31
source rpm(s):
ftp://ftp.suse.com/pub/suse/ppc/update/7.1/zq1/bind8-8.2.3-121.src.rpm
235e142413ec35bcbdb86168b04b7a78

SuSE-7.0:
ftp://ftp.suse.com/pub/suse/ppc/update/7.0/n1/bind8-8.2.3-121.ppc.rpm
44dc01f6b4fae1dfd87874db6d42e8d9
ftp://ftp.suse.com/pub/suse/ppc/update/7.0/n1/bindutil-8.2.3-121.ppc.rpm
d46f45bef0f12c3c5b071443ac9e7f13
source rpm(s):
ftp://ftp.suse.com/pub/suse/ppc/update/7.0/zq1/bind8-8.2.3-121.src.rpm
1bac32496ae66d4b0e35bc34d4e500ff

______________________________________________________________________________

2) Pending vulnerabilities in SuSE Distributions and Workarounds:

BIND4
In addition to the vulnerabilities in BIND8 discussed above, ISS
report several vulnerabilities in BIND4. As stated previously,
SuSE has discontinued support for BIND4 and recommends that
users upgrade to BIND8 as soon as possible.

Trojaned libpcap/tcpdump
There have been reports that the source packages of tcpdump and
libpcap available from several FTP servers have been modified to
include a trojan. We have checked our source packages for this
and found them to be clean.

______________________________________________________________________________

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 [email protected]),
the checksums show proof of the authenticity of the package.
We disrecommend to subscribe 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 un-installed 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 "[email protected]" upon installation or upgrade, provided that
the package gpg is installed. The file containing the public key
is placed at the top-level 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:

[email protected]
- general/linux/SuSE security discussion.
All SuSE security announcements are sent to this list.
To subscribe, send an email to
.

[email protected]
- SuSE's announce-only mailing list.
Only SuSE's security announcements are sent to this list.
To subscribe, send an email to
.

For general information or the frequently asked questions (faq)
send mail to:
or
respectively.

=====================================================================
SuSE's security contact is or .
The 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 clear-text signature shows proof of the
authenticity of the text.
SuSE Linux AG makes no warranties of any kind whatsoever with respect
to the information contained in this security advisory.

Type Bits/KeyID Date User ID
pub 2048R/3D25D3D9 1999-03-06 SuSE Security Team
pub 1024D/9C800ACA 2000-10-19 SuSE Package Signing Key


Newsletter signup

Signup to our monthly newsletter and stay in touch with IT news!

Free E-books

We've got ebooks! But they're not online. :( Please give us a few days to bring downloads back.

Contact

Have something to say or just wanna drop us a line? Please keep this in mind: to spam, we reply with spam.

Contact us »