Race condition in the ns_client structure management in ISC BIND 9.9.x before 9.9.1-P2 allows remote attackers to cause a denial of service (memory consumption or process exit) via a large volume of TCP queries.
https://kb.isc.org/article/AA-00730
http://www.slackware.com/security/viewer.php?l=slackware-security&y=2012&m=slackware-security.536004