The new version of bind uses a random transaction-ID (TRXID) and a random
UDP source-port for DNS queries to address DNS cache poisoning attacks
possible because of the "birthday paradox" and an attack discovered by Dan
Kaminsky. Unfortunately we do not have details about Kaminsky's attack and
have to trust the statement that a random UDP source-port is sufficient to
stop it.
______________________________________________________________________________
SUSE Security Announcement
Package: bind
Announcement ID: SUSE-SA:2008:033
Date: Fri, 11 Jul 2008 09:00:00 +0000
Affected Products: openSUSE 10.2
openSUSE 10.3
openSUSE 11.0
SUSE SLES 9
Novell Linux Desktop 9
Open Enterprise Server
Novell Linux POS 9
SUSE Linux Enterprise Desktop 10 SP1
SLE SDK 10 SP1
SLE SDK 10 SP2
SUSE Linux Enterprise Server 10 SP1
SUSE Linux Enterprise Desktop 10 SP2
SUSE Linux Enterprise Server 10 SP2
Vulnerability Type: DNS cache poisoning
Severity (1-10): 9
SUSE Default Package: no
Cross-References: CVE-2008-1447
Content of This Advisory:
1) Security Vulnerability Resolved:
DNS cache poisoning
2) Solution or Work-Around
3) Special Instructions and Notes
4) Package Location and Checksums
5) Pending Vulnerabilities, Solutions, and Work-Arounds:
6) Authenticity Verification and Additional Information
______________________________________________________________________________
1) Problem Description and Brief Discussion
The bind daemon is responsible for resolving hostnames in IP addresses and
vice versa.
The new version of bind uses a random transaction-ID (TRXID) and a random
UDP source-port for DNS queries to address DNS cache poisoning attacks
possible because of the "birthday paradox" and an attack discovered by Dan
Kaminsky. Unfortunately we do not have details about Kaminsky's attack and
have to trust the statement that a random UDP source-port is sufficient to
stop it.
DNS servers that do not support recursive queries or do not use a cache
(authoritative only servers) are not vulnerable too.
Update packages of bind9 for SLES8 will be available soon.
The glibc stub resolver is known to be vulnerable too and we will publish
updates as soon as possible.
Note, a local attacker can always sniff DNS queries and generate spoofed
responses easily.
If you use the UDP source-port number of the DNS server in your firewall
configuration, for example to let DNS queries through your packetfilter,
then you have to take steps to adapt your filter rules to the new behavior
of the DNS server.
2) Solution or Work-Around
To protect your infrastructure from cache poisoning attacks you should
provide two DNS servers.
One that is authoritative only and accessible from the Internet to resolve
queries for your local systems that are available over the Internet. The
other system (caching) is not accessible over the Internet and can be used
by internal clients to recursively lookup names and addresses.
But we encourage you to install the bind update as soon as possible too.
If you use the latest update of pdns-recursor you are not vulnerable to
this attack.
For the glibc stub resolver bug you can install a local secure DNS for-
warder on your machine or make a DNS forwarder available for a protected
network.
3) Special Instructions and Notes
Please restart the bind daemon after the update.
4) Package Location and Checksums
The preferred method for installing security updates is to use the YaST
Online Update (YOU) tool. YOU detects which updates are required and
automatically performs the necessary steps to verify and install them.
Alternatively, download the update packages for your distribution manually
and verify their integrity by the methods listed in Section 6 of this
announcement. Then install the packages using the command
rpm -Fhv
to apply the update, replacing with the filename of the
downloaded RPM package.
x86 Platform:
openSUSE 11.0:
http://download.opensuse.org/pub/opensuse/update/11.0/rpm/i586/bind-9.4.2-39.2.i586.rpm
http://download.opensuse.org/pub/opensuse/update/11.0/rpm/i586/bind-chrootenv-9.4.2-39.2.i586.rpm
http://download.opensuse.org/pub/opensuse/update/11.0/rpm/i586/bind-devel-9.4.2-39.2.i586.rpm
http://download.opensuse.org/pub/opensuse/update/11.0/rpm/i586/bind-doc-9.4.2-39.2.i586.rpm
http://download.opensuse.org/pub/opensuse/update/11.0/rpm/i586/bind-libs-9.4.2-39.2.i586.rpm
http://download.opensuse.org/pub/opensuse/update/11.0/rpm/i586/bind-utils-9.4.2-39.2.i586.rpm
openSUSE 10.3:
http://download.opensuse.org/pub/opensuse/update/10.3/rpm/i586/bind-9.4.1.P1-12.5.i586.rpm
http://download.opensuse.org/pub/opensuse/update/10.3/rpm/i586/bind-chrootenv-9.4.1.P1-12.5.i586.rpm
http://download.opensuse.org/pub/opensuse/update/10.3/rpm/i586/bind-devel-9.4.1.P1-12.5.i586.rpm
http://download.opensuse.org/pub/opensuse/update/10.3/rpm/i586/bind-doc-9.4.1.P1-12.5.i586.rpm
http://download.opensuse.org/pub/opensuse/update/10.3/rpm/i586/bind-libs-9.4.1.P1-12.5.i586.rpm
http://download.opensuse.org/pub/opensuse/update/10.3/rpm/i586/bind-utils-9.4.1.P1-12.5.i586.rpm
openSUSE 10.2:
ftp://ftp.suse.com/pub/suse/update/10.2/rpm/i586/bind-9.3.5P1-0.1.i586.rpm
ftp://ftp.suse.com/pub/suse/update/10.2/rpm/i586/bind-chrootenv-9.3.5P1-0.1.i586.rpm
ftp://ftp.suse.com/pub/suse/update/10.2/rpm/i586/bind-devel-9.3.5P1-0.1.i586.rpm
ftp://ftp.suse.com/pub/suse/update/10.2/rpm/i586/bind-doc-9.3.5P1-0.1.i586.rpm
ftp://ftp.suse.com/pub/suse/update/10.2/rpm/i586/bind-libs-9.3.5P1-0.1.i586.rpm
ftp://ftp.suse.com/pub/suse/update/10.2/rpm/i586/bind-utils-9.3.5P1-0.1.i586.rpm
x86-64 Platform:
openSUSE 11.0:
http://download.opensuse.org/pub/opensuse/update/11.0/rpm/x86_64/bind-libs-32bit-9.4.2-39.2.x86_64.rpm
openSUSE 10.3:
http://download.opensuse.org/pub/opensuse/update/10.3/rpm/x86_64/bind-libs-32bit-9.4.1.P1-12.5.x86_64.rpm
openSUSE 10.2:
ftp://ftp.suse.com/pub/suse/update/10.2/rpm/x86_64/bind-libs-32bit-9.3.5P1-0.1.x86_64.rpm
Sources:
openSUSE 11.0:
http://download.opensuse.org/pub/opensuse/update/11.0/rpm/src/bind-9.4.2-39.2.src.rpm
openSUSE 10.3:
http://download.opensuse.org/pub/opensuse/update/10.3/rpm/src/bind-9.4.1.P1-12.5.src.rpm
openSUSE 10.2:
ftp://ftp.suse.com/pub/suse/update/10.2/rpm/src/bind-9.3.5P1-0.1.src.rpm
Our maintenance customers are notified individually. The packages are
offered for installation from the maintenance web:
Open Enterprise Server
http://support.novell.com/techcenter/psdb/aa846ea840c9bf29e6974f3b6913e550.html
Novell Linux POS 9
http://support.novell.com/techcenter/psdb/aa846ea840c9bf29e6974f3b6913e550.html
Novell Linux Desktop 9
http://support.novell.com/techcenter/psdb/aa846ea840c9bf29e6974f3b6913e550.html
SUSE SLES 9
http://support.novell.com/techcenter/psdb/aa846ea840c9bf29e6974f3b6913e550.html
SUSE Linux Enterprise Server 10 SP1
http://support.novell.com/techcenter/psdb/555065b7278085ce1ce7a6e84b6f07aa.html
SUSE Linux Enterprise Server 10 SP2
http://support.novell.com/techcenter/psdb/555065b7278085ce1ce7a6e84b6f07aa.html
SLE SDK 10 SP2
http://support.novell.com/techcenter/psdb/555065b7278085ce1ce7a6e84b6f07aa.html
SUSE Linux Enterprise 10 SP2 DEBUGINFO
http://support.novell.com/techcenter/psdb/555065b7278085ce1ce7a6e84b6f07aa.html
SLE SDK 10 SP1
http://support.novell.com/techcenter/psdb/555065b7278085ce1ce7a6e84b6f07aa.html
SUSE Linux Enterprise Desktop 10 SP1
http://support.novell.com/techcenter/psdb/555065b7278085ce1ce7a6e84b6f07aa.html
SUSE Linux Enterprise Desktop 10 SP2
http://support.novell.com/techcenter/psdb/555065b7278085ce1ce7a6e84b6f07aa.html
______________________________________________________________________________
5) Pending Vulnerabilities, Solutions, and Work-Arounds:
none
______________________________________________________________________________
6) Authenticity Verification and Additional Information
- Announcement authenticity verification:
SUSE security announcements are published via mailing lists and on Web
sites. The authenticity and integrity of a SUSE security announcement is
guaranteed by a cryptographic signature in each announcement. All SUSE
security announcements are published with a valid signature.
To verify the signature of the announcement, save it as text into a file
and run the command
gpg --verify
replacing with the name of the file where you saved the
announcement. The output for a valid signature looks like:
gpg: Signature made using RSA key ID 3D25D3D9
gpg: Good signature from "SuSE Security Team "
where is replaced by the date the document was signed.
If the security team's key is not contained in your key ring, you can
import it from the first installation CD. To import the key, use the
command
gpg --import gpg-pubkey-3d25d3d9-36e12d04.asc
- Package authenticity verification:
SUSE update packages are available on many mirror FTP servers all over the
world. While this service is considered valuable and important to the free
and open source software community, the authenticity and the integrity of
a package needs to be verified to ensure that it has not been tampered
with.
The internal 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, replacing with the
filename of the RPM package downloaded. The package is unmodified if it
contains a valid signature from build@suse.de with the key ID 9C800ACA.
This key is automatically imported into the RPM database (on
RPMv4-based distributions) and the gpg key ring of 'root' during
installation. You can also find it on the first installation CD and at
the end of this announcement.
- SUSE runs two security mailing lists to which any interested party may
subscribe:
opensuse-security@opensuse.org
- General Linux and SUSE security discussion.
All SUSE security announcements are sent to this list.
To subscribe, send an e-mail to
.
opensuse-security-announce@opensuse.org
- SUSE's announce-only mailing list.
Only SUSE's security announcements are sent to this list.
To subscribe, send an e-mail to
.
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______________________________________________________________________________
The information in this advisory may be distributed or reproduced,
provided that the advisory is not modified in any way. In particular, the
clear text signature should show proof of the authenticity of the text.
SUSE Linux Products GmbH provides no warranties of any kind whatsoever
with respect to the information contained in this security advisory.