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bugtraq: FreeBSD Security Advisory FreeBSD-SA-07:07.bind

FreeBSD Security Advisory FreeBSD-SA-07:07.bind

From: FreeBSD Security Advisories <security-advisories_at_nospam>
Date: Wed Aug 01 2007 - 21:27:29 GMT
To: Bugtraq <bugtraq@securityfocus.com>


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FreeBSD-SA-07:07.bind Security Advisory The FreeBSD Project Topic: Predictable query ids in named(8) Category: contrib Module: bind Announced: 2007-08-01 Credits: Amit Klein Affects: FreeBSD 5.3 and later. Corrected: 2007-07-25 08:23:08 UTC (RELENG_6, 6.2-STABLE) 2007-08-01 20:44:58 UTC (RELENG_6_2, 6.2-RELEASE-p7) 2007-08-01 20:45:49 UTC (RELENG_6_1, 6.1-RELEASE-p19) 2007-07-25 08:24:40 UTC (RELENG_5, 5.5-STABLE) 2007-08-01 20:48:19 UTC (RELENG_5_5, 5.5-RELEASE-p15) CVE Name: CVE-2007-2926

For general information regarding FreeBSD Security Advisories, including descriptions of the fields above, security branches, and the following sections, please visit <URL:http://security.FreeBSD.org/>.

I. Background

BIND 9 is an implementation of the Domain Name System (DNS) protocols. The named(8) daemon is an Internet Domain Name Server. DNS requests contain a query id which is used match a DNS request with the response and to make it harder for anybody but the DNS server which received the request to send a valid response.

II. Problem Description

When named(8) is operating as a recursive DNS server or sending NOTIFY requests to slave DNS servers, named(8) uses a predictable query id.

III. Impact

An attacker who can see the query id for some request(s) sent by named(8) is likely to be able to perform DNS cache poisoning by predicting the query id for other request(s).

IV. Workaround

No workaround is available.

V. Solution

Perform one of the following:

  1. Upgrade your vulnerable system to 5-STABLE, or 6-STABLE, or to the RELENG_6_2, RELENG_6_1, or RELENG_5_5 security branch dated after the correction date.
  2. To patch your present system:

The following patches have been verified to apply to FreeBSD 5.5, 6.1, and 6.2 systems.

  1. Download the relevant patch from the location below, and verify the detached PGP signature using your PGP utility.

# fetch http://security.FreeBSD.org/patches/SA-07:07/bind.patch
# fetch http://security.FreeBSD.org/patches/SA-07:07/bind.patch.asc

b) Execute the following commands as root:

# cd /usr/src
# patch < /path/to/patch
# cd /usr/src/lib/bind
# make obj && make depend && make && make install
# cd /usr/src/usr.sbin/named
# make obj && make depend && make && make install

VI. Correction details

The following list contains the revision numbers of each file that was corrected in FreeBSD. Branch Revision   Path - ------------------------------------------------------------------------- RELENG_5 src/contrib/bind9/bin/named/client.c 1.1.1.1.2.5 src/contrib/bind9/lib/dns/dispatch.c 1.1.1.1.2.3 src/contrib/bind9/lib/dns/include/dns/dispatch.h 1.1.1.1.2.2 RELENG_5_5 src/UPDATING 1.342.2.35.2.15 src/sys/conf/newvers.sh 1.62.2.21.2.17 src/contrib/bind9/bin/named/client.c 1.1.1.1.2.3.2.1 src/contrib/bind9/lib/dns/dispatch.c 1.1.1.1.2.1.6.1 src/contrib/bind9/lib/dns/include/dns/dispatch.h 1.1.1.1.2.1.6.1 RELENG_6 src/contrib/bind9/bin/named/client.c 1.1.1.2.2.3 src/contrib/bind9/lib/dns/dispatch.c 1.1.1.1.4.2 src/contrib/bind9/lib/dns/include/dns/dispatch.h 1.1.1.1.4.1 RELENG_6_2 src/UPDATING 1.416.2.29.2.10 src/sys/conf/newvers.sh 1.69.2.13.2.10 src/contrib/bind9/bin/named/client.c 1.1.1.2.2.1.4.2 src/contrib/bind9/lib/dns/dispatch.c 1.1.1.1.10.2 src/contrib/bind9/lib/dns/include/dns/dispatch.h 1.1.1.1.10.1 RELENG_6_1 src/UPDATING 1.416.2.22.2.21 src/sys/conf/newvers.sh 1.69.2.11.2.21 src/contrib/bind9/bin/named/client.c 1.1.1.2.2.1.2.1 src/contrib/bind9/lib/dns/dispatch.c 1.1.1.1.8.1 src/contrib/bind9/lib/dns/include/dns/dispatch.h 1.1.1.1.8.1 - -------------------------------------------------------------------------

VII. References http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2007-2926 http://www.isc.org/sw/bind/bind-security.php http://www.trusteer.com/docs/bind9dns_s.html

The latest revision of this advisory is available at http://security.FreeBSD.org/advisories/FreeBSD-SA-07:07.bind.asc -----BEGIN PGP SIGNATURE-----
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