Security researchers have discovered several serious new vulnerabilities in the BIND software that runs on the vast majority of the Internet's DNS servers. The most serious flaw, a buffer overrun in both BIND 4 and BIND 8, enables an attacker to execute arbitrary code on a vulnerable server.
http://www.eweek.com/article2/0,3959,696200,00.asp
http://www.eweek.com/article2/0,3959,696200,00.asp