Critical vulnerability in BIND 9 regular expression handling
It has been revealed that a malicious regular expression can cause a denial-of-service of the open source BIND DNS server on Linux and Unix systems. Other programs using BIND's libdns are also potentially vulnerable to the same attack. The critical bug allows attacker to cause excessive memory consumption by the named process which could lead to the daemon using all available memory on the affected machine; this could lead to the crashing of BIND and detrimentally affect other services running on the same server.
You don't need to be a genius to debug a pf.conf firewall ruleset, you just need the guts to run tcpdump