By default, cpanel doesn’t disable recursive queries on your DNS server. This can, I believe, opens the door to possible attacks.
To be on the safe side, just edit the /etc/named.conf file and add the following lines, where ip1, ip2, etc, are replaced with the actual IPs of your server :
// added : http://forums.cpanel.net/showpost.php?p=217540&postcount=27
acl "trusted" {
ip1;
ip2;
127.0.0.1;
};
options {
// following from http://forums.cpanel.net/showpost.php?p=217540&postcount=27
version "not currently available";
allow-recursion { trusted; };
allow-notify { trusted; };
allow-transfer { trusted; };
};