This indicates an attack attempt to exploit a Denial of Service vulnerability in ISC BIND.
The vulnerability results from an error in the server process "named". A remote attacker can exploit this to cause a Denial of Service condition.
ISC BIND 9.8.0
ISC BIND 9.8.0-P1
ISC BIND 9.8.0-P2
ISC BIND 9.8.1b1
Denial of Service: Remote attackers can crash vulnerable systems.
Apply the most recent upgrade or patch from the vendor.