There has been a big effort underway by security researcher Dan Kaminsky on a very bad problem with many DNS server platforms. Basically, it's a poisoning attack, and a fairly bad one from what is being said. Mr. Kaminsky will publish full details after his presentation at the Black Hat conference. A list of affected systems are in
CERT VU #800113.
Note that all versions of ISC BIND are affected, but only version 9 is patched. I guess version 8 is too difficult to fix. If you still have version 8 servers, put in place a plan to upgrade to version 9. Also note that this affects servers with recursion enabled, so if you are running authoritative servers, disable recursion on them - it's a good practice anyway.
Most vendors should have updated their packages with patched ones by now, so if you use the vendor-supplied BIND, you just need to make sure you are updated. If you are running from source, you should be running 9.3.5-P1, 9.4.2-P1, or 9.5.0-P1.
