Some of internet's largest firms involved in the internet have moved quickly to fix what is described as a fundamental flaw within the DNS.

The flaw, discovered by internet security expert Dan Kaminsky earlier this year, was hurriedly addressed by Microsoft and Cisco, among others. When the flaw was discovered by Kaminsky, he gathered the affected parties together to discuss the problem and work out a fix rather than publicise it to give hackers a chance to exploit it. The severity of the flaw, he says, "is shown by the number of people who've gotten onboard with this patch."

Virtually every domain name server that resolves IP addresses on the Internet is vulnerable to the flaw and needs to be patched against it as quickly as possible to avoid potentially serious problems, such as companies having all of their network traffic rerouted to malicious Web sites or having employee emails captured by attackers, according to Kaminsky reported Computerworld.

The flaw works, reports IDG, "by sending certain types of queries to DNS servers, the attacker could then redirect victims away from a legitimate website to a malicious website without the victim realising it. This type of attack, known as DNS cache poisoning, doesn't affect only the Web. It could be used to redirect all Internet traffic to the hacker's servers." The bug could be exploited "like a phishing attack without sending you e-mail," said Wolfgang Kandek, chief technical officer with security company Qualys.

However the flaw may have been discovered as much as three years ago by a student reports The Register. "Three years ago Ian Green, then studying for his GIAC Security Essentials Certification (GSEC), submitted a paper that details the same DNS spoofing vulnerability, the SANS Institute's Internet Storm Centre notes."

A list of media reports for more indformation is below:

Computer hackers: Internet flaw sparks biggest security fix in web history
www.guardian.co.uk/technology/2008/jul/10/hacking.internet

The glitch explained
www.guardian.co.uk/technology/2008/jul/10/hacking.internet1

Tech giants unite to thwart web hijack risk
technology.timesonline.co.uk/tol/news/tech_and_web/article4301557.ece

Patch domain name servers now, says DNS inventor
computerworld.com/action/article.do?command=viewArticleBasic&articleId=9108378

An Astonishing Collaboration by Dan Kaminsky
www.circleid.com/posts/87920_an_astonishing_collaboration/

Massive, coordinated DNS patch released
news.cnet.com/8301-10789_3-9985618-57.html
news.cnet.com/8301-10789_3-9985815-57.html

DNS hole prompts synchronized patching effort by IT vendors
computerworld.com/action/article.do?command=viewArticleBasic&articleId=9107978

Leading vendors team up to squash DNS bug [IDG]
techworld.com/security/news/index.cfm?newsid=102110

Shocker DNS spoofing vuln discovered three years ago by a student
www.theregister.co.uk/2008/07/09/dns_bug_student_discovery/