FreeBSD Security Advisory – BIND 9 is an implementation of the Domain Name System (DNS) protocol. The named daemon is an Internet Domain Name Server. The libdns library is a library of DNS protocol support functions. Due to a software defect, specially constructed zone data could cause named to crash with an assertion failure and rejecting the malformed query when DNSSEC validation is enabled. An attacker who can cause specific queries to be sent to a nameserver could cause named to crash, resulting in a denial of service.