During the past few weeks we have been hearing more about a severe DNS cache poisoning vulnerability that threatens to become a major problem if it's not promptly dealt with. A lot of interesting information was released on the flaw post-fix, detailing some of the potential attacks that could be executed. While the core problem was identified and fixed, there is evidence of attempts to exploit this flaw in the wild.
Several sources are indicating that attacks have increased since publicly available exploits were unveiled, and that the ultimate concern is that many ISPs remain vulnerable due to the lack of up to date software. There are numerous tools available on the web to check if the DNS servers you are using are susceptible. But with an infinite number of small ISPs, the concern is that they might not ever update, leaving their users at risk.