Feeds

Patched DNS servers still vulnerable to cache poisoning

But the sky won't fall just yet

Security for virtualized datacentres

Large swaths of the internet remain at risk from a potentially crippling vulnerability in the net's address lookup system even after installing emergency patches, a researcher has warned.

Russian researcher Evgeniy Polyakov posted exploit code here, which he says allowed him to poison domain-name system servers running the most recent version of the Berkeley Internet Name Domain (BIND), the most popular software for translating domain names into numeric IP addresses. The attack, which poisons the records of domain-name system servers with incorrect information, could allow criminals to silently redirect millions of users to fraudulent websites that attempt to steal login credentials or install malware.

Researchers who spearheaded an international push to get internet service providers and other large organizations to patch the flaw said they weren't terribly concerned about the exploit code. That's because Polyakov's attack took 10 hours to carry out using two machines connected directly to the targeted DNS server via a gigabit ethernet link.

"That's a little different then spending 10 seconds over the internet," to carry out an attack, said Dan Kaminsky, the researcher who first warned of the DNS cache poisoning vulnerability.

The original attack works by flooding a DNS server with thousands of requests for domains with slightly different variations, 1.google.com, 2.google.com, 3.google.com and so forth. That allows attackers to gain a secret transaction number needed to trick other computers into updating their records with IP addresses that lead to rogue websites.

Successful attacks took seconds to carry out using 10-megabit connections. The patch to BIND and other DNS programs randomizes the source ports used, vastly reducing the odds an attacker will gain the transaction credentials.

"We have successfully made the attack significantly less likely to occur in the real world," Kaminsky told The Register. "That doesn't mean the defense is perfect." He said the patch should be thought of as a "stopgap" until more thorough changes can be made to the net's DNS.

So a word to the Googles, Microsofts and Ciscos of the world: You dodged a bullet in surviving the Kaminsky bug with nary a scrape, but next time you may not be as lucky. Forging a real fix won't be easy, but it's essential. Time to get cracking. ®

Secure remote control for conventional and virtual desktops

Whitepapers

Forging a new future with identity relationship management
Learn about ForgeRock's next generation IRM platform and how it is designed to empower CEOS's and enterprises to engage with consumers.
Why cloud backup?
Combining the latest advancements in disk-based backup with secure, integrated, cloud technologies offer organizations fast and assured recovery of their critical enterprise data.
Win a year’s supply of chocolate
There is no techie angle to this competition so we're not going to pretend there is, but everyone loves chocolate so who cares.
High Performance for All
While HPC is not new, it has traditionally been seen as a specialist area – is it now geared up to meet more mainstream requirements?
Intelligent flash storage arrays
Tegile Intelligent Storage Arrays with IntelliFlash helps IT boost storage utilization and effciency while delivering unmatched storage savings and performance.