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Security The Internet Worms IT

Worms Could Dodge Net traps 58

Danse writes "ZDNet reports that future worms could evade a network of early-warning sensors hidden across the Internet unless countermeasures are taken. According to papers presented at the Usenix Security Symposium, just as surveillance cameras are sometimes hidden the locations of the Internet sensors are kept secret. From the article: 'If the set of sensors is known, a malicious attacker could avoid the sensors entirely or could overwhelm the sensors with errant data.' A team of computer scientists from the University of Wisconsin wrote up the background in their award-winning paper titled 'Mapping Internet Sensors with Probe Response Attacks.'"
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Worms Could Dodge Net traps

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  • by rritterson ( 588983 ) * on Sunday August 07, 2005 @03:50AM (#13262710)
    Duh! Of course you can slowly figure out how a security system works, and then work around it. See any famous and/or talented thief for such an example. The real threat, I suppose, is that these worms can do it automatically and on a larger scale.

    Solution: Don't open holes and then fill them with trip wires. Just fill up the hole (via patch or otherwise) in the first place.
  • But... (Score:2, Insightful)

    This still doesn't protect the users that are spreading the worms in the first place. So you make an announcement about a worm on the loose? They don't even know what the updates do, and don't patch themselves. The early warning has protected itself.
    • hopefully people at the core level of system administration (backbones, major isps, etc) will become clueful enough to shoot these packets to the local equivalent of /dev/null
  • Quick Summary (Score:5, Interesting)

    by Shadowlore ( 10860 ) on Sunday August 07, 2005 @03:59AM (#13262744) Journal
    Maintaining sensor anonymity is critical because if the set of sensors is known, a malicious attacker could avoid the sensors entirely or could overwhelm the sensors with errant data.'

    So basically: "Security through Obscurity is Bad." combined with "We found a way to eliminate the obscurity.".

    • Re:Quick Summary (Score:3, Informative)

      by aussie_a ( 778472 )
      "We found a way to eliminate the obscurity.".

      Sorry, but I'm not seeing where the obscurity is eliminated. The entire article basically says "It's easy to make Internet Network Sensors not work by easily identifying them (can be done in a week) and then avoiding them." The only solution the article offers is:

      The threat could be diminished, both studies said, if the information in the networks' public reports was less detailed.

      Which to me is saying "If the network's public information was obscured a
  • by Biomechanical ( 829805 ) on Sunday August 07, 2005 @04:02AM (#13262751) Homepage

    ...We have roving Intrusion Countermeasures (Or IC) inside our system. Not just passive measures, but semi-autonomous active measures.

    We already have a form of White IC - simple detection, non-aggressive measures. How long before we have more active Grey IC - Tar Babies (similar to today's honey pots), Tar Pits, Blaster - and ultimately, Black IC - seeking out the source of the intrusion and in turn, destroying the origin of attack?

    Would a big, multi-national corporation get punished for "accidentally" frying the computer of someone who was thought to be intruding into the corporation's computers? I seriously doubt it.

    • Somebody's been reading too much Gibson :-D

      However right you might be :-D
      • Actually I nicked them from Shadowrun. :)

        Even if you're not into Role Play Games, in particular pencil and paper ones, check out the section on the Matrix in Shadowrun - no, it's not a knock-off of the movie, Shadowrun was first written some time in the early to mid eighties.

        Despite the computer models being very different from real life, a lot of the ideas for security and counter-security are things that seem to be popping up these days.

        Apologies for bad definitions. It's been a while since I pl

        • Ahh, I'm familiar with Shadowrun, however, heres some trivia for you. The Matrix was nicc'ed from Gibsons novels :-D

          I don't know what the timeline is, but Gibson is creditted with it first, and talks about Black ICE attacking hackers in Neuromancer and several other novels, where it can also kill people in the matrix. The system then goes on to follow a hacker around the physical world through various mechanations.
          • I'm familiar with Case, I've got Neuromancer, Count Zero, Mona Lisa Overdrive, and Burning Chrome. I did have All Tomorrow's Parties too but it disappeared one day from my flat.

            It didn't click that FASA used Gibson's Matrix. They're similar, but I never thought to piece them together because Gibson's is more vague than the FASA extrapolation - but of course FASA's going to expand on it, they're making it into a "real" thing. :)

            Here's a funny co-incedence (sp?). I was watching a documentary today on t

    • "someone who was thought to be intruding" is the killer though. Would it be easier to attack Microsoft directly, or to make eBay think they were being attacked by Microsoft and let their countermeasures attack Microsoft?
    • > Would a big, multi-national corporation get punished for "accidentally" frying the computer of someone who was thought to be intruding into the corporation's computers? I seriously doubt it.

      It makes for a nice story, but how do you find the cracker's computer?
      If you fry the computers who attack you, you have 99% of chance of frying the computers of guys who are only guilty of not having secured their PC enough..
      And this *would not* be without consequence (assuming the corporation get caught).
      • That's one of the things I've been thinking about - unsecured, remotely controlled or pre-scripted drones being used as launch points for an attack.

        Seriously, a corporation such as Monsanto, Microsoft, IBM, Nestle, Douwe-Egberts, wouldn't give a shit about who's attacking them, just stopping the attack.

        If something comes to the publics attention, "It's jonesy's fault! He took personal, unauthorised measures to retaliate."

        As a whole, The Corporation doesn't give a shit. It will "live on", so to spe

        • >"It's jonesy's fault! He took personal, unauthorised measures to retaliate."

          And why would jonesy accept to be a scapegoat in the ensuing trial?
          If he has a brain, he kept traces of what he was ordered to do, for his own protection.

          Plus you underestimate the effect of that bad publicity may have on companies.
    • Would a big, multi-national corporation get punished for "accidentally" frying the computer of someone who was thought to be intruding into the corporation's computers?

      I'm sure McDonalds wishes every time they spill coffee on someone that the "It was an accident!" and "I'm a big, multi-national corporation! Haven't you read any cyberpunk? We're above the law, and have private armies!" mattered a hill of beans to an ambulance-chaser with a license to sue. Or see burglers who sued after being injured in

    • How long before we have more active Grey IC - Tar Babies (similar to today's honey pots), Tar Pits, Blaster - and ultimately, Black IC - seeking out the source of the intrusion and in turn, destroying the origin of attack?

      Is that name serious? "Tar Babies"? I ask because it is also a racial slur intended as a play on the dark skin of black people. An older slur, but nonetheless still used (my redneck former boss used it frequently.)

      Call me a p.c. asshole if you want, but if you grew up in the sout

  • Again?! (Score:4, Interesting)

    by Arkan ( 24212 ) on Sunday August 07, 2005 @04:03AM (#13262754)
    Is it just me, or are we again speaking about security through obscurity (albeit I have to admin that it's in a slightly different way, this time).

    How long will it take for people involved in computers and networks security that "secret" has no virtually no meaning in the field?

    A private key is the only exception I can see at the moment: it is kept secret because nobody has any use of it except its owner, a noone will ever need access to it.

    But how long a "secret" early-warning network will remain so... when its primary function is to be contacted by the worms that try to evade it?

    • Re:Again?! (Score:4, Interesting)

      by jd ( 1658 ) <imipak AT yahoo DOT com> on Sunday August 07, 2005 @04:46AM (#13262845) Homepage Journal
      AFAICT, you are correct - the private key of a private/public key pair is about the only true secret, as virtually all other information is shared at some time or other.

      I suppose it is arguable that load-balancing and fail-over systems are "secrets" in a sense, as external users aren't supposed to see that information, but I'd call them "null secrets" in the sense that they have no value even if you DID know them.

      Presumably these early-warning systems are some kind of a mix of honey-pots and passive sniffers. If the worm is actually any good, it should be able to infiltrate a honey-pot and become stealthy (thus undetectable to anything inside the honey-pot). In that case, the system running the honey-pot would be able to detect an infection occured, but would NOT have reliable data on how or when.

      As for passive sniffers, a polymorphic worm that can vary the loading code as well as the payload, OR a worm that is encrypted and can hijack some OS internal decrypt code, would get past such a sniffer. There'd be nothing the sniffer could identify.

      The "ultimate" in malware would be some sort of hypervisor - similar in idea to Xen - that could "run" the host OS on top of itself. That way, nothing inside the OS could see it and all calls to the hardware that would reveal the malware could be trapped. Some early DOS boot sector viruses did something similar, copying the original boot sector to an empty sector somewhere else and then marking it bad to safeguard it. Any time a call was made to look at the boot sector, the call was trapped and the copy was returned instead of the real one.

      The "ultimate" transport mechanism for malware would use a decoder built into the OS. The LZW code for GIF images, perhaps. Just something that would make it impossible for virus scanners in a mail server, or sniffers on a network, to use simple pattern recognition to identify it. You'd then need a buffer overflow you could exploit to take your newly decrypted malware into the system itself.

      Image decoder exploits and buffer overflow exploits are well-known and have certainly been utilized in the past, though I'm not sure if in this way. Polymorphic code, designed to make identification strings next to impossible, has also been around a long time. I think the first polymorphic viruses appeared in the late 1980s and were certainly a significant cause of concern in the early 1990s.

      Of course, if Cisco doesn't fix that IOS bug soon, it'll all be moot anyway. If you can just capture one Cisco router at a time, in a chain, you can set up tunnels to carry whatever you damn well feel like. An IPSec tunnel would be utterly opaque to any monitoring system anyone cared to deploy, no matter how sophisticated.

      All in all, security through hidden monitors - security through several layers of obscurity - is no security at all, as it is simply too easy to bypass the layers involved and therefore the monitors, without having to know a damn thing about where the monitors are or even how they do the monitoring.

  • Passive scanning? (Score:1, Informative)

    by Anonymous Coward
    If these are used solely for detecting, rather than taking action and blocking traffic, why on earth aren't they located passively? By that I mean a ethertap [snort.org]. rather than having a device sat on the line that responds to traffic.
    That would essentially make the device invisible - all you'd then have to do is have your network of passive detectors inform you when odd traffic passes through.
    • Re:Passive scanning? (Score:3, Informative)

      by Mnemia ( 218659 )
      These are passive sensors.

      What the paper refers to is sites that publish information about network traffic they see. Some print tables with statistics and others generate graphs of network traffic levels. Their technique is basically a way to map where the passive listening points are based on the traffic reports these sites create. They strategically generate traffic which creates measurable spikes, and these show up in the reports. They use this information to determine where the listeners are.
      • Maybe I just haven't woken up fully, but I don't see why a passive sensor would be generating any traffic visible to the outside world...
        • No, the attackers are generating the traffic spikes, the sensors passively pick it up. Then the attackers can lurk on the public stats and logs to find out the locations of the sensors.
          • Yeah, I get that. But why are the sensor owners making the data public?? Trying to puff up their own importance, maybe?? Should we be accusing them of generating the traffic spikes, just we sometimes accuse anti-virus companies of manufacturing viruses to keep themselves in business??

            I wonder if they're reporting all the traffic?? Maybe they're not, in order to funnel attackers into supposedly unwatched areas?? Heh, tinfoil hat time again...:)

  • First penetration testing, and now this?
    ...with Probe Response Attacks...

    The original penetration story:
    http://books.slashdot.org/article.pl?sid=05/07/25/ 200221&tid=172&tid=6 [slashdot.org]

  • DSheild Discussion (Score:3, Informative)

    by tjohns ( 657821 ) on Sunday August 07, 2005 @04:24AM (#13262798) Homepage
    A similar article by zdnet.co.uk was brought up a few days ago on the DShield discussion list [dshield.org]. One choice quote is from Johannes Ullrich, a member of the SANS Internet Storm Center [sans.org] and the developer of DShield:

    We do receive reports from about 500-700k IP addresses each day.
    Including the full list would be hard (or make for a very large worm).
    In addition, many of these IPs are dynamic, so you have to exclude
    networks rather then individual IPs.

    To put it down bluntly: If every IP is a sensor, there is nobody left to
    attack ;-)

    For those of you who don't know, DShield [dshield.org] is precisely one of the 'early-warning sensor' networks the article is talking about.
    • The ususal botnet configuration is such that bots get their instructions to scan IP ranges from a central place. It isn't too difficult to add a "sensor database" to the botnet infrastructure.

      Dynamic IPs and computers entering and/or leaving sensor networks complicate the case of mapping out the sensor network. Furthermore, in the real world not every probe package will be reported. Mapping out a subset of the sensor network and pollute it with false data is pretty easy. Mapping out the full network to avo

  • Awesome, another cat and mouse game.
  • wow (Score:2, Insightful)

    a really good read. i knew it would be a matter of time before something like this can be thwarted, basically attacks are slowly evolving. would it be easy for them to change to different unused IP addresses?

    i know an easy fix.. i see in the paper "bandwidth for the fractional T3 attacker and the OC6 attacker could be achieved by using around 250 and 2,500 cable modems".. i wish more cable ISPs were responsive to abuse complaints, or would notice certain bot-like activity like many DDoS attacks coming fr
    • Bandwidth is a lot cheaper than all the hardware and staff costs to get a system like that working. Why should the isp have ot fork out a ton of money to deal with stupid users?
  • Shout out to the my boys and girls at the U-Dub. I'm gonna go strap on my kevlar so i survive being shot down for off-topic.
  • by jurt1235 ( 834677 ) on Sunday August 07, 2005 @04:55AM (#13262857) Homepage
    A biological virus adapts to its environment too, a worm too, so why would the digital variant not adapt. And since the main platform clearly suffers from an immune deficiency syndrom, just kept alive by their doctors and creators by means which are always to late to stop the newest infection but just on time to save most patients, it is pretty easy for the virusses to stay alive, and adapt to a point where the immune system will completely fail.
  • Solution: Needs more sensors.

    If the number of sensors is brought to the point where it becomes impractical to map them, voila no more sensor evasion.

    This obviously would be harder to impliment than spoken. Maybe if a sensor implimentation came as an optional standard with server software.

    Heh, I can speculate.

    • > Maybe if a sensor implimentation came as an optional standard with server software.

      Sounds good until you consider that with massive deployment of sensors (especially those bundled with OS) it'd be impossible to manage them properly.

      We could easily end up with compromised sensor network, hacker-induced fake alerts and god-know-what.
  • Or alternatively (Score:4, Insightful)

    by Rosco P. Coltrane ( 209368 ) on Sunday August 07, 2005 @05:01AM (#13262870)
    Could certain software companies start spewing out secure software, so worms don't have much of a chance to exist in the first place?

    The number of companies getting fat over those needless insecurities is just gross...
  • by pe1chl ( 90186 ) on Sunday August 07, 2005 @05:41AM (#13262953)
    For a long time I have forwarded all 419 scams to abuse addresses at all their involved mailbox hosters.
    In some cases (not always, unfortunately) this causes them to lose their account and thus their way to get replies and possible revenue.

    What I would have liked is that they detected "when we send mail to this address we lose our account" and put that address on some blacklist to send no more scams.

    But, this has not happened. So, I don't think there is any cleverness behind it, they just scatterbomb and hope the don't hit a whistleblower.
  • I want to suggest one thing ,in my opinion very important..

    We're talking all the time about security of internet,about net-monitoring ,packets filtering, and what really irritates me IPv6 security.
    Please note that nobody complain about such solutions everyone believes that they're (or will be) elegant and helpful.
    My questuion is..what do you think goverment(NSA) will do with such 'security tools' ha?
    So we're not talking about security but we're also talking about Privacy and Freedom of internet-
  • What about creating an ad hoc distributed network of sensors (versus a fixed network). If thousands or millions of people downloaded a worm monitor application, then the sensor network would be very fluid and span IP space in a less predictable way. An ongoing P2P cross-comparison of the signatures of unsolicited packets could also provide distributed detection of novel worms. When too many sensors see the same anomalous thing, the alert propagates across the network.

    Done well, it would create an int
    • If wanted to attack such a system, I would flood it with so much false data that you couldn't tell the fake from the real. If people fed the data from such a system into an IPS, where they take actions to block "suspect" packets, it would make for a great DoS tool. Think of it -- use your bot-net to fake reports of attacks from port 80 from microsoft.com.
  • When I saw the thread title, I only thought of real worms (you know, the squirmy squishy things in that big blue room that has way too few accessible electrical outlets) and fishing nets.
  • Basically, they are saying that by probing ports in particular patterns, and then looking for mention of their probes in published summary reports, they can determine the identity of systems contributing to the reports. (If a trivial idea like that manages to get the USENIX best paper award, then it's no wonder computer security is so bad.)

    I, for one, hope that these kinds of techniques will be widely adopted by worm writers. Why? Because it sets up an incentive system to have systems monitored and contri

Beware of Programmers who carry screwdrivers. -- Leonard Brandwein