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Cybercriminals Building New, Stealthier Networks 107

ancientribe writes "Cybercriminals are adopting a new method of hiding and sustaining their malicious Websites and botnet infrastructures so they'll be harder to detect, called "fast-flux," according to an article in Dark Reading. Criminal organizations behind two infamous malware families — Warezov/Stration and Storm — in the past few months have separately moved their infrastructures to so-called fast-flux service networks. The article says bad guys like fast-flux not only because it keeps them up and running, but also because it's more efficient than traditional methods of infecting victims' machines." I'm not exactly sure why this is new/different than the more well known open relay proxy networks.
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Cybercriminals Building New, Stealthier Networks

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  • Block TCP Port 80 (Score:5, Insightful)

    by quanticle ( 843097 ) on Wednesday July 18, 2007 @09:35AM (#19899953) Homepage

    What can be done about fast flux? ISPs and users should probe suspicious nodes and use intrusion detection systems; block TCP port 80 and UDP port 53; block access to mother ship and other controller machines when detected; "blackhole" DNS and BGP route-injection; and monitor DNS, the report says.

    The bit about blocking TCP port 80 is troubling. I run a small web-site for learning purposes and to share info with family and friends. I don't especially like the possibility of having to ask or pay extra to have port 80 opened on my end.

    • Re: (Score:3, Insightful)

      by brunes69 ( 86786 )
      So run it on port 8080 or something else. There is nothing magical about port 80 that you have to run a website on it.
    • Re: (Score:2, Interesting)

      Charter.net blocks port 80. It was PITA to figure out why I couldn't connect to my webserver from outside the Charter network. While inside their network I could just fine. Once I figured it out though, its was as simple as moving the webserver to a different port. I picked 443 because they allow secure websites. From there I just set up a little domain forwarding/cloaking so that end users never see they are connected to 443 and don't use SSL - its not needed for the type of site I have hosted.
    • Re: (Score:3, Interesting)

      by CastrTroy ( 595695 )
      I've never got why people want to run a webserver on their home computer over a cheap cable/dsl connection. I tried it for a while but between the cost of the extra computer, the cost of the extra electricity, the trouble of setting up all the server software on my own, and the trouble of dealing with changing IPs, and all the other wonderful cable ISP network oddities, I found it easier to just pay a cheap monthly fee for a shared hosting account. It's nice to run a home server for some things, but if it
      • I'm amazed that you were modded a troll for expressing your justified opinion in a non confrontational manner.. guess I'll have to not take it so personally next time it happens to me!
        • by geniusj ( 140174 )
          Overflow from digg? :-\
        • Troll Post, noun:
          1. A post expressing a different opinion that that of the moderator.
          2. A post not read or comprehended by the moderator.
          3. A post that was intended as a joke and was not found funny by the moderator.
      • Prozac time! Or at least some decent coffee. It's not the OP's fault that you haven't gotten laid.

        Oh, and can we at least try for some reading comprehension? That's a perfectly reasonable statement and makes no mention whatsoever of Microsoft, Apple, Google or George Bush.

      • I find it's a great way to share information with friends if you happen to use IRC as your preferred means of digital communication instead of IM.

        Maintain a nonstandard port webserver with a dummy index.html file, dump any files you'd like to share with friends in there, have a little alias script which fills in the blanks with your site address (like "/myweb whatever.jpg") and then let rip.

        It's a lot easier to show people what your most recent project is without having to deal with crap lik
        • Vi and Emacs have more features than you imagine.
        • Agreed withthe sentiment plus one extra thing: there's no point to shell out for 9GB of hosting space for the ONE dvd-iso I'd like make accessible to the ONE person who's ever going to download it. On my home machine it'll clog up the tubes overnight and that's all it ever needs.

          And then there is

          This is assuming you're not completely hardcore and do all of your PHP/HTML/CSS in vi or emacs instead of a more modern code editor

          I use emacs. I never realized that made me "hardcore".

          (code collapse, color highlighting, and completion is your friend).

          emacs had done all this since the eighties. So?

      • by Fweeky ( 41046 )
        I have plenty of my own hosting (several racks, a few dozen machines), but I still run a webserver at home.

        A large part of it is that it's easy, and the machine and software it lives on would exist anyway (I'm a web developer, among other things). I find it a good place to dump low priority things which I don't want to faff about dealing with remotely; like, photos. I could easily be using GB's of disk space with photos hardly anyone will bother to look at, and that can add up rapidly on a server which ma
        • So basically you're saying what I said. For stuff that's just used within your house, definitely a home server makes sense. But for stuff that others are going to be accessing from outside your house, shared hosting can get rid of a lot of issues. Even using your home server as a staging area for the stuff you put up on you shared hosting account is a good idea. So, I'm not saying that nobody should be running a home server, just that I don't see the usefulness of using it as a machine that the whole wor
      • Because we're nerds, so it's neat to do? Or because it's a great way to learn about networks?
      • mythtv (more specifically mythweb), zoneminder, slimserver spring to mind as possible reasons to run your own web server,
        being able to set mythtv to record any tv program for you, check your cctv camera's at home and access your music collection from anywhere in the world seems reason enough to run a webserver.
        obviously you don't make these services available to the general public, but if the pc is going to be on anyway why not.

        I would agree that if you want to run a public website then pay
      • by caluml ( 551744 )
        I've never got why people want to run a webserver on their home computer over a cheap cable/dsl connection

        Then you're not the person to offer opinions on it.
        Software versions? Diskspace? are just two off the top of my head.
    • Re:Block TCP Port 80 (Score:5, Interesting)

      by Anonymous Coward on Wednesday July 18, 2007 @10:49AM (#19901005)
      With power comes responsibility. If you want unfettered internet access, it's your responsibility to make sure that your participation in this network doesn't cause problems for others. Since most residential internet users have neither the ability nor the intention to shoulder that responsibility, their upstream provider has to find ways to protect other internet users from his customers, because if he doesn't, he will ultimately have to pay for the damage that they do (higher traffic costs, less favorable peering agreements, blacklisting, etc.)

      The net has grown very fast and so far we've shirked the responsibility issue: Customer's complain about spam and when the spammer's provider says it's not their responsibility, they're called a safe-haven for spammers. On the other hand, when customers get cut off because their computers are scanning and infecting other machines, they complain that it's not their fault and how are they supposed to keep their system clean without a full time admin and it's none of the ISPs business as long as the internet access bills are paid.
    • What can be done about fast flux? ISPs and users should probe suspicious nodes and use intrusion detection systems; block TCP port 80 and UDP port 53; block access to mother ship and other controller machines when detected; "blackhole" DNS and BGP route-injection; and monitor DNS, the report says.

      The bit about blocking TCP port 80 is troubling. I run a small web-site for learning purposes and to share info with family and friends. I don't especially like the possibility of having to ask or pay extra to have port 80 opened on my end.

      What's wrong with asking for port 80 to be turned on? Does your email not work? Do you have a problem with your gob? Hell, they could even automate it on a web site asking for your username/password/mothers maiden name/name of first pet and you can do it there.

      You silly lazy git.

      You sure as hell shouldnt have to pay for it, but you don't like the possibility of asking? *sheesh*

  • So, in the end (Score:2, Interesting)

    by vivaoporto ( 1064484 )
    These criminals are giving a "smarter" * use for the enormous potential that these hundred thousands of homogeneous (or similar enough) connected machines have than most companies out there does. It is time for 1) Microsoft and its users get their act straight and work on better security for they machines and 2) someone to realize the incredible potential of all this "dark" bandwidth and processing power and give it a good use. Criminals are showing it is possible, all it need is some legitimate application
    • There are ways of utilising the bandwidth for good purposes, there's SETI(good if you believe that your bandwidth can actually find aliens) and Folding@Home(a bit more useful, helps understand diseases development)
    • With regard to point 2, have you never heard of folding@home or world community grid? Or did I miss understand what you were saying?
      • The dark fiber is dark, and the unused cycles are unused, not because there aren't enough good reasons to use them, but because there aren't enough economically profitable reasons to use them. Folding@home may cure disease, but if doesn't make a buck...scratch that, if it doesn't maximize revenue as part of a dynamic global strategy to leverage something or other, then they can't be bothered. Making a buck isn't enough anymore.
    • It is time for 1) Microsoft and its users get their act straight and work on better security for they machines
      Given that Windows has hundreds of millions (if not billions) of users, and that a significant portion run pirated versions (and therefore avoid installing all flavors of patches), how exactly do you expect all of them to close up their machines? Do you suddenly expect the Chinese, Koreans, and others to have a conscience about this kind of shit?
    • These criminals are giving a "smarter" * use for the enormous potential that these hundred thousands of homogeneous (or similar enough) connected machines have than most companies out there does. It is time for 1) Microsoft and its users get their act straight and work on better security for they machines and 2) someone to realize the incredible potential of all this "dark" bandwidth and processing power and give it a good use. Criminals are showing it is possible, all it need is some legitimate application.

      Yes, it's time the Empire of Nastiness started to use its powers for good instead of evil.

    • In the end this really does scare me. My husband has a terrible habit of surfing for porn (yeah guys chuckle all you want, doesn't bother me too much). He does use Firefox, and I've got Adblock installed, but still I'm positive something is wrong in there. All the antivirus checks are negative, no rootkits found using the f-secure BlackLight, and the sysinternals rootkit detector. But just have a sinking horrible feeling something isn't "right". Check out my blog http://toriauru.blogspot.com/ [blogspot.com] to see wh
      • My friend's computer has been acting funny lately as well. The firewall reports (and stops) outbound connection attempts on unusual ports to seemingly random IP addresses at seemingly random intervals, even when the computer is completely idle otherwise. Virus scan with AVG and Norton - nothing. Spybot S&D, AdAware - nothing. Rootkit Revealer - nothing. HijackThis - nothing. ADSRevealer - nothing. Startup list viewer - nothing.

        Yet, still with the random connection attempts.

        The traffic is coming from l

        • Yeah, that's the scary thing, that a semi-competent person like myself, just knows enough to know what's wrong, but not how to fix it. I'm dreading yet another wipe, and reinstall, but sure enough, that's really the only great way to fix it all. Ugh, such a fucking pain in the arse. Sorry, yes, I do know Linux, and Ubuntu is *safer* but I do need Windows for certain things. I can't just completely switch to Linux like that *snaps fingers*. It's taking time for me to learn it all.
        • Pull the drive, and hook it into a known-good system. Boot from the other disk, and run your tests from there. Nothing gets run from the infected drive, so you should get a clear picture of what's really there.
          • Okay, will try that. Thanks. :) (and thanks for the no-attitude reply like why don't you use Linux all the time stuff) :P
    • by Abuzar ( 732558 )
      Dude, criminals are kewl, we wouldn't have civilization without them :)
  • News at 11 (Score:1, Flamebait)

    by spikedvodka ( 188722 )
    translate: Scum of the earth trying to stay 1 step ahead of kings horses & men

    News at 11
  • The essence of the article really boils down to "botnet herders may have the ability to update their DNS info quickly".
    Possibly makes it incrementally harder to track down every last one of the pwned machines, a tad more if your logs store only resolved names but no IP addresses.

    Most /.ers likely knew this already, but I imagine this may be exciting and scary to some suits.

    In other words, the world did not change much due to this.
  • "I'm not exactly sure why this is new/different than the more well known open relay proxy networks."

    ... which just goes to show that even spammers can fall victim to their own marketing:

    Tired of your botnets getting killed off? Use fast-flux. See a 30% increase in only 2 days. She'll love you for it!.
  • by Control Group ( 105494 ) * on Wednesday July 18, 2007 @09:50AM (#19900159) Homepage
    I am not a networking guru (IANANG, copyright 2007, me, all rights reserved), so I'd appreciate somebody setting me straight on this if necessary.

    But I don't really see how blocking port 80 would be an effective way to fight this sort of thing. There's nothing special about port 80 aside from it being the default http port. Unless the victims are typing the URL into their address bar, I don't see any reason the mother ship couldn't have bots listen on another port. I mean, the machine is already owned, so it's not like opening up port 43783 is difficult. And I can't help believing that most - if not all - people going to these sites are clicking links, not typing addresses.

    So you close off port 80, and anyone running a legit (well, probably not, given the TOS of most ISPs, but at least not a malicious) web server out of their house/apartment/dorm room can no longer easily direct people to it. Meanwhile, the malicious sites are slowed down by the amount of time it takes some jackass to change one constant in one piece of code.

    Unless, of course, there's some other factor I'm unaware of making it more difficult to reach an http host over something other than port 80.
    • I'm not saying it's a good idea. But the intruders do need some way to access the machine at will. If they leave a port listening, the OS knows and can tell the user (netstat) or firewall it unless the OS is also compromised. If the OS is compromised, it still wouldn't be long until somebody figures it out and massive blocking on that port could occur by ISPs (as is being suggested). The bot could poll some website to update itself, such as triggering a switch listening on a new port, but that would be
      • by Control Group ( 105494 ) * on Wednesday July 18, 2007 @10:27AM (#19900699) Homepage

        Randomly select a different port each time you connect to the zombie. If you're really worried about users running netstat to check their open ports (and I suspect that zombied machines are more often owned by people who don't even know the CLI exists, much less who generally run network diagnostic tools via the CLI than not - and by a wide margin), then have it only open the port for ten minutes every hour. Windows, by default, updates its clock to NIST weekly, so you can be reasonably sure that your zombies are synced enough for that to work. Round-robin assign the ten minute window to the zombies (xx:00 - xx:09, xx:01 - xx:10, xx:02 - xx:11, etc). During that window, you use the zombie to host content, and you can push a listen port update. At any given time, most of your zombies are running on the same port (they have to be, or your victims can't connect to your content), but blocking that port will only be effective for however long you determine. How fast can ISPs identify a rogue port and block it?

        If my experience with spam is any indication, the linked sites go down almost as fast as the spam comes in, but that's (apparently) not a problem for the spammers. So you rotate ports every two, three days.

        And this is just the scheme I've come up with off the top of my head in less than a minute.

        Come to think of it, you're already executing arbitrary code on the zombied machine. Have them determine when they can listen on their assigned port, with a minimum frequency and duration set, with a bias towards times the user isn't at the console. When the window opens, step one is to notify the mother ship that this machine is active.

        There are probably holes in this scheme, but I don't see the problem as being intractable. I do see any effort to just block port 80 as being naive (at best). I don't think ISPs can respond fast enough to block a new port every couple days, but perhaps I'm wrong about that.
    • Re: (Score:2, Informative)

      by GnuDiff ( 705847 )
      AFAI have looked, port 80 is the one that is least likely to be stopped by firewalls.

      There are a number of small (and I mean tiny - think 100 clients max) ISPs around my city alone, whose networking expertise is close to nil. They go with default settings of the equipment they get. So even if they put up a firewall of sorts to protect their clients, it is left at default settings.

      The fact is there are not only tons of users out there without a clue, but a nice bunch of ISPs as well and sloppy network admins
    • by orclevegam ( 940336 ) on Wednesday July 18, 2007 @10:21AM (#19900597) Journal
      The blocking of port 80 they suggest really isn't about stopping the fast flux network, but it's an attempt to make it harder (marginally) to use the systems on that network for phishing attacks. As I understand it one of the uses these networks are being put to is to duplicate a phishing site on a couple hundred zombie systems, then rotate a single phishing URL through all of them making it harder to bring down the phishing site because you'd have to take down every one of the zombies, or find some way of nuking the DNS entry (which apparently the registrars are hesitant to do, even though some recent events seem to show that they'll do it quite happily if a big enough company or corporation asks them to). Personally I think blocking port 80 is a dumb idea and barely constitutes a speed bump for the kinds of people that run these things, but hey, that's never stopped a company from adopting a stupid idea, or marginal positive value and substantial negative (to the customer, if it hurts their bottom line forget it).
  • by Anonymous Coward on Wednesday July 18, 2007 @10:17AM (#19900535)
    Has a lot more detail: http://www.honeynet.org/papers/ff/fast-flux.html [honeynet.org]
  • Child porn, illegal websites, etc...

    Yawn. How many techies didn't see this coming?

    But it will make a great coffee-table conversation topic...

    Them: So you don't run Windows? Why not?

    Me: Because I don't like supporting child porn.

    And then the conversation will turn to how criminals use vulnerabilities in Windows to conduct their illicit affairs.

  • Nothing to see here.

    No, seriously. Cybercriminals fast-fluxed my gag and now I've got nuttin'.
  • How about ISPs try the obvious:
    block the DNS for known phishing sites.

    e.g. Spam filter raises a warning to an e-mail that invites you to visit manlynessenhancer.biz.
    Solution: in ISP's DNS route manlynessenhancer.biz to a warning site that says:
    This is known phishing site, we've blocked it for Your protection.
    • by uolamer ( 957159 ) *
      I prefer my ISP not block anything period. I dont want my ISP determining what ports, what services, websites, etc that I can use. ISPs to me should simply provide me with internet that is all. If they are providing e-mail they can have whatever spam/anti-virus/etc stuff they want on it, since im not using it anyways. I'm not installing their 'software' if they have any. etc. All i want is a ethernet plug that through whatever magical means gets the 'internet to me'. I will take care of the rest.. but i kno
    • by cshake ( 736412 )
      The possibility for misuse on the ISP side is enormous. Do you really want an ISP to be able to arbitrarily block any websites?
      What if they decide that some perfectly legal politically charged website shouldn't be viewed? I'd rather have unlimited access and have to worry about the results myself, thankyouverymuch. Censorship is almost never a good thing.
  • by Todd Knarr ( 15451 ) on Wednesday July 18, 2007 @01:11PM (#19903417) Homepage

    Fast-flux takes advantage of the ability to set extremely low time-to-lives on DNS resource records. The shorter the TTL, the faster changes propagate out through the DNS cache network. This suggests a way of neutering fast-flux: implement a minimum TTL in DNS servers. Since most people depend on their ISP's DNS servers rather than going directly to the roots, this would effectively prevent the fast-flux record changes from propagating as fast as they need to to be effective. If, for example, an ISP put a 30-minute minimum TTL in place, then the A record for a given name would remain fixed for 30 minutes (modulo cache being filled and the record being forced out) regardless of what the fast-flux network did. And since the DNS servers enforcing the minimum typically aren't under the control of either the botnet or the infected machines, there's nothing the botnet operators can do about the situation. As a side-effect, this also cuts the load on the DNS network caused by PHBs who order 60-second TTLs on their records "so customers won't be inconvenience when we change our IP addresses".

    Two glitches with the idea:

    1. Changes to the NS records for a domain are also slowed down. When changing your NS records you need to make the changes but leave the old servers running in parallel long enough for the changes to trickle out to everybody.
    2. Load balancing via round-robin DNS would be broken unless the caching servers also do rotation of the cached records in responses. I think BIND already does that.
  • Defense is legal, Offense is illegal, and why? "I don't know." THIRD-BASE!

    My logic, you need defense to be able to do what you need/want to do (like go on the offense).
    Also, you need offense to prevent others from doing what you don't want them to do (like they can't go on offense).

    IOW: The real purpose of defensive action is to provide force/operations security, until offensive action is possible.

    Intel/CoOps (like chicken "coops") are a defensive actions that disrupt the ability of others to take a success
    • The only problem with going on the offensive is who to go on the offensive against. On a computer network it's fairly easy for the attacker to mask his identity behind that of third parties who don't even know they're being used, and it's very hard for the attacked party to tell whether any given attacker is a real one or merely an unwitting dupe (and all but impossible to determine who the true party behind it all is). If you lash out at a large number of parties who didn't realize they were involved in an

      • Collateral damage is caused with defensive and "offensive" actions. In modern warfare defense is always the losing position. We need to start looking at how to identify and terminate the problem ... take the war to the enemy until unconditional surrender.

        Putting band-aids/stitches to keep the dirt out and allow healing is defensive, there will always be broken glass and sharp objects available to crackers, phreakers ... for tossing into public places and school grounds. I never blame science, technology, to
  • by jbsoles ( 1129855 ) on Wednesday July 18, 2007 @02:27PM (#19904563)
    As the subject implies, fast-flux networks are not proxies. They HAVE proxies. The basic difference is that a proxy redirects incoming and outgoing traffic through a server or router some where else, thus "spoofing" your IP address. Fast-flux networks certainly use proxies, but there's one big difference; fast-flux networks allow you to host content this way. To host your own website (short of technical mastery) you used to need a static IP address that runs directly to one or more servers, making it very easy to catch you if you use a domain name for illegal purposes and even easier to shut you down. Fast-flux networks allow you to use many IP addresses to host content from one central server or set of servers. The IP's on the front end are disposable and more can be generated quickly. It also provides the web site administrator a proxy level to protect his identity while hosting just like the one Tor proxy provides me while surfing. In other words, the difference between fast-flux networks and proxies is that fast-flux networks can be used to host from one computer to many different IP addresses, in part by using proxies. A proxy just doesn't let you do that. Thanks for reading a rather long post. I'm a student and a paper on fast-flux networks just happened to be distributed where I do research for the summer:)
  • Why not use fast-flux against the botnet itself? If I know that a certain website is being hosted by a rotating array of bots, then I just query the IP address of the website every 30 seconds or so and the spammer will, over time, reveal the IP address of every bot in his network. That's got to be useful somehow, especially if you could work with the ISPs to have them notify the owners of the compromised machines, or block them if necessary (although that kind of cooperation may be a vain hope).
  • by Jerry ( 6400 ) on Wednesday July 18, 2007 @04:06PM (#19905987)
    ALL of these zombies are computers running a Windows OS.

    There. I've said it. Why hide the truth?

    Are journalist thinking "everyone knows it is Windows that is so vulnerable to mere emails, so there's no use in embarrassing Microsoft"? I don't think so... any more than they "just happened" to get Ferrari laptops for writing good articles about VISTA.

A committee takes root and grows, it flowers, wilts and dies, scattering the seed from which other committees will bloom. -- Parkinson