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Malware on Hijacked Subdomains, a New Trend?

Posted by Soulskill on from the hiding-in-plain-sight dept.

The Unmask Parasites blog discusses a technique attackers are using more and more often recently: modifying a compromised site's DNS settings to redirect various subdomains to different IPs that serve up malware, often leaving site administrators none the wiser. Quoting: "It is clear that hackers have figured out that subdomains of legitimate websites are an almost infinite source of free domain names for their attack sites. With access to DNS settings, they can create arbitrary subdomains that point to their own servers. Such subdomains can hardly be noticed by domain owners who rarely check their DNS records after the initial domain configuration. And they cost nothing to hackers. I wonder if using hijacked subdomains of legitimate websites is a new trend in malware distribution or just a temporarily solution that won't be widely adopted by cybercriminals in the long run (like dynamic DNS domains last September)."

12 of 24 comments (clear)

  1. Also done with 404 Error Documents by Anonymous Coward · · Score: 5, Informative

    This is also done with 404 Error pages. They change it to redirect to their spam, and then point people at what looks like a legitimate URL. Then they get redirected to the spam and are none the wiser. www.slashdot.org/thisdoesntexist could redirect anywhere.

    1. Re:Also done with 404 Error Documents by Anonymous Coward · · Score: 4, Informative

      Agreed 404, 301, 302. Anything that you can drop a .htaccess file into an account.

      Ideally, web servers (not just DNS) have a lot of holes, allowing NS access to the user isn't the problem like the TFA implies. Because most automation software doesn't allow for too much sub domain specific flexibility, most times you still need to be in root to redirect at a dns level.

      The exception is say parking (godaddy etc) or zoneedit but usually once its hosted it's pretty much in the hands of the admin to delegate externally.

    2. Re:Also done with 404 Error Documents by DeadPixels · · Score: 3, Informative

      While I've yet to personally see any subdomain hijacking, I have come across 404 pages that have been turned into drive-by-downloads. Otherwise legitimate sites have all of these extra pages created (www.example.com/search_query_here) that actually just point to malware. While most of them are still fairly easy to pick out because the domain is entirely unrelated to the search term, it's still dangerous and could easily catch many unobservant users.

    3. Re:Also done with 404 Error Documents by commodore64_love · · Score: 2, Interesting

      So can these hacks be used to get around "NoScript"? I currently have it set to:

      - Temporarily allow top-level sites by defualt
      --- Base 2nd level Domains (noscript.net)

      --
      "I disapprove of what you say, but I will defend to the death your right to say it." - historian Evelyn Beatrice Hall
  2. Wildcard SSL by oztiks · · Score: 2, Interesting

    Since a lot of hosting automation software (cPanel) sets up an a name for @ giving the power singularly to apache also lends it self to have the ability to mask it as being secure.

    It isnt a nameserver its moreover a webserver one.

  3. Administrator negligence? by davidwr · · Score: 3, Insightful

    "who rarely check their DNS records"

    And thereinlies both the problem and the solution.

    --
    Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
    1. Re:Administrator negligence? by oztiks · · Score: 3, Insightful

      I see the best way is to notify admin upon a dns change, any external sites added get sent via email.

      (sounds like a job for the guys at http://www.configserver.com/)

  4. unravel the illicit infrastructure by Anonymous Coward · · Score: 4, Insightful

    Yes, checking the DNS records will help identify the sites that have been modified, however it will also identify the hackers servers IP numbers. With that thread, you can start to unravel the illicit infrastructure, and counteract it.

    1. Re:unravel the illicit infrastructure by drdrgivemethenews · · Score: 2, Interesting

      At least in the example given, it would seem pretty feasible to do this at the GoDaddy site itself, where all the A records are centralized. How many businesses registered with GoDaddy have subdomains in different class A or even class B networks?

  5. That explains idle.slashdot.org by orkysoft · · Score: 5, Funny

    That explains idle.slashdot.org :-)

    --

    I suffer from attention surplus disorder.
  6. As a malware defense professional.. by ma1wrbu5tr · · Score: 5, Informative

    I can verify that this trend has been building for months. It only seems to be getting worse. We've logged literally hundreds of compromised sites ranging from the very high traffic to the very obscure. This is one case where even vigilant users are undermined by the lack of security awareness of the site admins.

    --
    Why can't we go back to using jumpers to configure slot adapter cards? Why? I say!
  7. Misread headlines by DigitAl56K · · Score: 2, Funny

    "Malware on Hijacked Submarines, a New Trend?"

    Talk about a double-take! Would have made for an interesting story, though :)