The remote host is missing an update to the system as announced in the referenced advisory FreeBSD-SA-06:20.bind.asc
Upgrade your system to the appropriate stable release or security branch dated after the correction date https://secure1.securityspace.com/smysecure/catid.html?in=FreeBSD-SA-06:20.bind.asc
BIND 9 is an implementation of the Domain Name System (DNS) protocols. The named(8) daemon is an Internet domain name server. DNS Security Extensions (DNSSEC) are additional protocol options that add authentication and integrity to the DNS protocols. For a recursive DNS server, a remote attacker sending enough recursive queries for the replies to arrive after all the interested clients have left the recursion queue will trigger an INSIST failure in the named(8) daemon. Also for a a recursive DNS server, an assertion failure can occour when processing a query whose reply will contain more than one SIG(covered) RRset. For an authoritative DNS server serving a RFC 2535 DNSSEC zone which is queried for the SIG records where there are multiple SIG(covered) RRsets (e.g. a zone apex), named(8) will trigger an assertion failure when it tries to construct the response.