The details were posted on a well-read blog July 21 despite Kaminsky's plans to keeping the specifics of his discovery secret until the Black Hat conference in August. A hacker can use a DNS attack to redirect page requests to phishing sites or other malicious pages

Hacking community Computer Academic Underground released "Kaminsky DNS Cache Poisoning Flaw Exploit" that credited Kaminsky with discovering "this exploit [which] targets a fairly ubiquitous flaw in DNS implementations which allow the insertion of malicious DNS records into the cache of the target nameserver," according to the documentation. It goes on to publish code with which to exploit this flaw.

CAU released "Kaminsky DNS Cache Poisoning Flaw Exploit for Domains" this week, which expands on the previous exploit. It describes how the DNS insertion completely replaces the original nameserver records for the target domain.

Ernst & Young senior security advisor Nathan McFeters blogged this week that the most significant development was that the hacker will gain "control over an entire domain, whereas the original hijacked an individual host."

Kaminsky has been urging IT workers to implement patches to protect this potentially dangerous loophole. In a Black Hat webcast, Kaminsky said within the first days after the patch was released, "86 percent of people testing their DNS servers were vulnerable. As of the last couple days, there is now 52 percent of DNS servers being tested that are still vulnerable."

Microsoft (microsoft.com) released a security patch earlier in the month to deal with the security vulnerability, that has since needed some modifications by security vendors such as Check Point Software (checkpoint.com) that issued a fix for its ZoneAlarm personal firewall that revives Internet connections affected by patch number KB951748.