Boffins devise early-warning bot spotter

Conficker's Achilles Heel


Researchers have devised a way to easily detect internet names generated by so-called domain-fluxing botnets, a method that could provide a first-alarm system of sorts that alerts admins of infections on their networks.

Botnets including Conficker, Kraken and Torpig use domain fluxing to make it harder for security researchers to disrupt command and control channels. Malware instructs infected machines to report to dozens, or even tens of thousands, of algorithmically generated domains each day to find out if new instructions or updates are available. The botnet operators need to own only a few of the addresses in order to stay in control of the zombies. White hats effectively must own all of them.

It's a clever architecture, but it has an Achilles Heel: The botnet-generated domain names – which include names such as joftvvtvmx.org, ejfjyd.mooo.com, and mnkzof.dyndns.org – exhibit tell-tale signs they were picked by an algorithm rather than a human being. By analyzing DNS, or domain name system, traffic on a network, the method can quickly pinpoint and disrupt infections.

“In this regards, our proposed methodology can point to the presence of bots within a network and the network administrator can disconnect bots from their C&C server by filtering out DNS queries to such algorithmically generated domain names,” the researchers wrote in a paper that was presented this week at the ACM Internet Measurement Conference in Australia.

The method uses techniques from signal detection theory and statistical learning to detect domain names generated from a variety of algorithms, including those based on pseudo-random strings, dictionary-based words, and words that are pronounceable but not in any dictionary. It has a 100-percent detection rate with no false positives when 500 domains are generated per top-level domain. When 50 domains are mapped to the same TLD, the 100-percent detection rate remains, but false positives jump to 15 percent.

The technique was developed by Sandeep Yadav, Ashwath K.K. Reddy, and A.L. Narasimha Reddy of Texas A&M's Electrical and Computer Engineering department, and Supranamaya Ranjan of Sunnyvale, California-based Narus. A PDF of their paper is here. ®

Broader topics


Other stories you might like

  • Experts: AI should be recognized as inventors in patent law
    Plus: Police release deepfake of murdered teen in cold case, and more

    In-brief Governments around the world should pass intellectual property laws that grant rights to AI systems, two academics at the University of New South Wales in Australia argued.

    Alexandra George, and Toby Walsh, professors of law and AI, respectively, believe failing to recognize machines as inventors could have long-lasting impacts on economies and societies. 

    "If courts and governments decide that AI-made inventions cannot be patented, the implications could be huge," they wrote in a comment article published in Nature. "Funders and businesses would be less incentivized to pursue useful research using AI inventors when a return on their investment could be limited. Society could miss out on the development of worthwhile and life-saving inventions."

    Continue reading
  • Declassified and released: More secret files on US govt's emergency doomsday powers
    Nuke incoming? Quick break out the plans for rationing, censorship, property seizures, and more

    More papers describing the orders and messages the US President can issue in the event of apocalyptic crises, such as a devastating nuclear attack, have been declassified and released for all to see.

    These government files are part of a larger collection of records that discuss the nature, reach, and use of secret Presidential Emergency Action Documents: these are executive orders, announcements, and statements to Congress that are all ready to sign and send out as soon as a doomsday scenario occurs. PEADs are supposed to give America's commander-in-chief immediate extraordinary powers to overcome extraordinary events.

    PEADs have never been declassified or revealed before. They remain hush-hush, and their exact details are not publicly known.

    Continue reading
  • Stolen university credentials up for sale by Russian crooks, FBI warns
    Forget dark-web souks, thousands of these are already being traded on public bazaars

    Russian crooks are selling network credentials and virtual private network access for a "multitude" of US universities and colleges on criminal marketplaces, according to the FBI.

    According to a warning issued on Thursday, these stolen credentials sell for thousands of dollars on both dark web and public internet forums, and could lead to subsequent cyberattacks against individual employees or the schools themselves.

    "The exposure of usernames and passwords can lead to brute force credential stuffing computer network attacks, whereby attackers attempt logins across various internet sites or exploit them for subsequent cyber attacks as criminal actors take advantage of users recycling the same credentials across multiple accounts, internet sites, and services," the Feds' alert [PDF] said.

    Continue reading

Biting the hand that feeds IT © 1998–2022