Vulnerability Note VU#927905
BIND version 8 generates cryptographically weak DNS query identifiers
ISC BIND version 8 generates cryptographically weak DNS query IDs which could allow a remote attacker to poison DNS caches.
The Berkeley Internet Name Domain (BIND) is a popular Domain Name System (DNS) implementation from Internet Systems Consortium (ISC). Version 8 of the BIND software uses a weak algorithm to generate DNS query identifiers. This condition allows an attacker to reliably guess the next query ID, thereby allowing for DNS cache poisoning attacks.
ISC states that this bug only affects outgoing queries, generated by BIND 8 to answer questions as a resolver, or when it is looking up data for internal uses, such as when sending NOTIFY messages to slave name servers. Note that although this vulnerability is similar in nature and impact to VU#252735, it is a distinct issue.
A remote attacker with the ability to predict DNS query IDs and respond with arbitrary answers, could poison DNS caches.
Upgrade or apply a patch
Users should obtain a patch from their operating system vendor when available. Please see the Systems Affected section of this document for more information about specific vendors.
Users who compile their own versions of BIND 8 from the original ISC source code are encouraged to take the following actions described by ISC:
This issue is addressed in ISC BIND 8.4.7-P1, available as patch that
can be applied to BIND 8.4.7.
The more definitive solution is to upgrade to BIND 9. BIND 8 is being
declared "end of life" by ISC due to multiple architectural issues.
See ISC's website at http://www.isc.org for more information and
If you are a vendor and your product is affected, let
us know.View More »
|Vendor||Status||Date Notified||Date Updated|
|Internet Software Consortium||Affected||21 Aug 2007||27 Aug 2007|
|BlueCat Networks, Inc.||Not Affected||27 Aug 2007||28 Aug 2007|
|Infoblox||Not Affected||27 Aug 2007||27 Aug 2007|
|Mandriva, Inc.||Not Affected||27 Aug 2007||27 Aug 2007|
|Microsoft Corporation||Not Affected||27 Aug 2007||28 Aug 2007|
|Apple Computer, Inc.||Unknown||27 Aug 2007||27 Aug 2007|
|Check Point Software Technologies||Unknown||27 Aug 2007||27 Aug 2007|
|Conectiva Inc.||Unknown||27 Aug 2007||27 Aug 2007|
|Cray Inc.||Unknown||27 Aug 2007||27 Aug 2007|
|Debian GNU/Linux||Unknown||27 Aug 2007||27 Aug 2007|
|EMC Corporation||Unknown||27 Aug 2007||27 Aug 2007|
|Engarde Secure Linux||Unknown||27 Aug 2007||27 Aug 2007|
|F5 Networks, Inc.||Unknown||27 Aug 2007||27 Aug 2007|
|Fedora Project||Unknown||27 Aug 2007||27 Aug 2007|
|FreeBSD, Inc.||Unknown||27 Aug 2007||27 Aug 2007|
Thanks to the
Internet Systems Consortium
(ISC) for reporting this vulnerability. ISC, in turn, credits
Amit Klein from
for reporting this issue to them.
This document was written by Chad Dougherty.
27 Aug 2007
Date First Published:
28 Aug 2007
Date Last Updated:
28 Aug 2007
If you have feedback, comments, or additional information about this vulnerability, please send us email.