ISC reports a cache poisoning flaw reported by Michael Sinatra of UC Berkeley that may cause bind to cache replies that were not properly DNSSEC validated when recursive query was done based on uncommon client query. A nameserver with DNSSEC validation enabled may incorrectly add records to its cache from the additional section of responses received during resolution of a recursive client query. This behavior only occurs when processing client queries with checking disabled (CD) at the same time as requesting DNSSEC records (DO). This issue was reported to affect all 9.x versions and should be fixed in 9.4.3-P4, 9.5.2-P1 and 9.6.1-P2.
While this flaw exists in all 9.x versions, we do not plan to release bind updates for Red Hat Enterprise Linux 3 and 4 including this fix. Version shipped in those products is 9.2.4 with too old DNSSEC implementation, which is incompatible with currently used DNSSEC version and can not be used to secure communication with current public internet DNS servers. This flaw does not introduce additional risks to bind installations not using DNSSEC, as successful attack requires bypass of other cache poisoning protections (such as random query source ports and transaction ids). This flaw only allows bypass of the protection provided by DNSSEC.
Public now via upstream advisory: https://www.isc.org/node/504 Also tracked by US CERT as VU#418861: http://www.kb.cert.org/vuls/id/418861
bind-9.6.1-7.P2.fc11 has been submitted as an update for Fedora 11. http://admin.fedoraproject.org/updates/bind-9.6.1-7.P2.fc11
bind-9.6.1-13.P2.fc12 has been submitted as an update for Fedora 12. http://admin.fedoraproject.org/updates/bind-9.6.1-13.P2.fc12
Fedora 10 requires this fix as well.
bind-9.6.1-7.P2.fc11 has been pushed to the Fedora 11 stable repository. If problems still persist, please make note of it in this bug report.
bind-9.6.1-13.P2.fc12 has been pushed to the Fedora 12 stable repository. If problems still persist, please make note of it in this bug report.
(In reply to comment #12) > Fedora 10 requires this fix as well. Fedora 10 will hit EOL in 2009-12-17 and two packages will have to be rebuilt against updated BIND. I think this fix is not needed in the end of life cycle of the Fedora 10.
This issue has been addressed in following products: Red Hat Enterprise Linux 5 Via RHSA-2009:1620 https://rhn.redhat.com/errata/RHSA-2009-1620.html
Statement: While this flaw exists in all 9.x versions, we do not plan to release bind updates for Red Hat Enterprise Linux 3 and 4 including this fix. The version of bind shipped in those products is 9.2.4, which has an older DNSSEC implementation, which is incompatible with currently used DNSSEC version and can not be used to secure communication with current public internet DNS servers. This flaw does not introduce additional risks to bind installations that are not using DNSSEC, as a successful attack requires bypass of other cache poisoning protections (such as random query source ports and transaction ids). This flaw only allows for the bypass of protection provided by DNSSEC.