In addition to upgrading to the newly patched versions of BIND, administrators should make sure their name servers restrict access to recursion.

Re: Users urged to patch serious hole in BIND 9 DNS server.

It's much easier to exploit this vulnerability on a name server that will process arbitrary recursive queries, since you can induce it to query a name server under your control or cause it to look up a domain name you want to spoof.

For more information on limiting access to recursion, may I suggest the two links at the bottom of our DNS Resources page, http://www.infoblox.com/library/dns_resources.cfm