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Distributive Worm Blocking

wdebruij writes "According to this source (unfortunately in dutch), a number of dutch ISPs are bundling their forces to fight the spread of worms. The technology, called virbl, blocks all accesses from IP addresses from which at least 2 worms were sent for 24 hours, naturally excluding known large email servers. Background info on the project can be found at the developers' project site. So, does anyone have useful remarks on why this may succeed or fail? It appears to me as a simple to implement yet powerful, albeit stopgap, solution."

24 of 162 comments (clear)

  1. Zegnar by Zegnar · · Score: 5, Insightful

    Here is progress - still I imagine many companies will leave things as they are just to avoid having to deal with irate calls to the helpdesk, and carry on broadcasting viruses to the world. Collective defense is fine until it costs money.

    1. Re:Zegnar by mattyrobinson69 · · Score: 4, Interesting

      when freeserve depreciated one of their dial-up numbers, all attempts to access port 80 were forwarded to their http server on a page which explained how to change the number, and what to. - they blocked all other connections i think.

      pain in the arse, but it could be useful if the same kind of thing was implemented if you were showing characteristics of running a worm, to redirect you to their free online virus scanner (or somebody elses). that way, you cant infect anybody else, but you can still use the online vius scanner to remove virus's (using an OCX).

      this will carry on working, while nearly all worms are for windows. i imagine most people with other os's wouldn't get hit, not because of higher security neccessarily, but because they wouldn't spread well in a world where 90%+ boxes are windows, and even then, the less than 10% of boxes isn't one OS - there's mac, linux, free/open/net bsd, solaris, etc.

    2. Re:Zegnar by icedivr · · Score: 3, Interesting

      Perhaps a partial block could be instituted - allow only outbound http to Windows Update.

  2. a new denial of service attack by pedantic+bore · · Score: 4, Interesting
    Now all you need to do is trick someone into sending you something that resembles a worm... (all it will take for some trickster to add a rule the worm signature files that says that all messages that contain
    ^Dear
    ).

    It seems like a good idea, but it seems like the threshold is too low and there ought to be a human in the loop (i.e., if the system suddenly decides to block half the IP numbers in the universe, a human should have to OK it).

    Unfortunately I don't read Dutch; maybe they've thought of this already.

    --
    Am I part of the core demographic for Swedish Fish?
    1. Re:a new denial of service attack by pedantic+bore · · Score: 5, Insightful

      It does say that they "exlude known large email servers" so presumably it would be hard to take out an ISP. But it sounds like you could DHCP-hop your way through a an address bank and make things pretty miserable for someone.

      --
      Am I part of the core demographic for Swedish Fish?
    2. Re:a new denial of service attack by AndroidCat · · Score: 3, Insightful

      No, just the people trying to send mail directly from DHCP addresses, which are frequently blocked anyway. Hopefully this would put more pressure on ISPs to find and disconnect their infected customer before they poison more addresses for a day or two.

      --
      One line blog. I hear that they're called Twitters now.
  3. Re:Security by shutdown? by Roguelazer · · Score: 5, Funny

    Or, you could just post a link on slashdot to all infected systems. Same end effect.

  4. Re:Not gonna work! by RidiculousPie · · Score: 3, Informative

    Did you even think about reading the article?

    The program provides a list of ip addresses to block email from. It doesn't only target dutch isp customers email, it allows email from known virus offenders to be blocked.

    Also in the faq for the program, a dutch ISP can apply to be whitelisted.

    So how does this constitute locking down their customers?

    In addition, do ISPs want virus spreading customers?

    --
    ah, mod points ... now where is my crack?
  5. Frea Speach! by AndroidCat · · Score: 5, Insightful

    The same people who complain when their ISP is blocked for sending spam will (no doubt) complain that this blocks their constitutional right to run an infested box on the Internet--complete with examples of how innocent people will be hurt by this. (Hmm, how about DHCP dynamic addresses?)

    --
    One line blog. I hear that they're called Twitters now.
  6. This is a sensible thing to do but.... by Sox2 · · Score: 5, Insightful

    how do users then download the patches to deal with the infection? Not everyone on the internet is computer literate; will the ISPs provide some help to these people?

    1. Re:This is a sensible thing to do but.... by AndroidCat · · Score: 3, Insightful

      This project only blocks incoming email from infected IP addresses. It doesn't block outgoing web access, so MS Update should still run. This is limited because it won't stop true worms that don't use email to spread, but it will reduce the load on email virus scanners: Rather than checking each email, they can do a quick lookup on the IP address after it's detected as a virus source.

      --
      One line blog. I hear that they're called Twitters now.
  7. Re:That's not security, that's stupidity. by [Lizard] · · Score: 5, Informative

    Ehm, not really, the system also uses a whitelist on which the mailservers of normal ISPs are listed.
    Furthermore a bot-created smtp will trigger the protection quick enough so it won't be able to send much. Personally I doubt it will backfire, but maybe there's some place for improvements, time will tell.

    (When I have some free time I'll try to translate the article in readable english :)

  8. Re:Dutch DOS by AndroidCat · · Score: 5, Insightful

    If you can IP spoof with a TCP/IP connection, you could do a lot more damage than a DoS attack.

    --
    One line blog. I hear that they're called Twitters now.
  9. We already had this in the NL by Anonymous Coward · · Score: 3, Funny

    We already have a system based on killing your internet access whenever you do something stupid. We call it "Chello" and being subscribed to it is considered very stupid/ A viscious, though effective, circle.

    I don't hate my ISP. Not at all. I love my cable internet with upload speeds that would make an ISDN user laugh...

  10. We use a similar concept @ work by jsav40 · · Score: 5, Informative

    Infected machines are locked out of the network entirely. Getting the machines reconnected is a fairly lengthy process and users have become *much* more interested in allowing field techs to patch machines since the lockdown process was initiated. We push patches out remotely so only 5% or so of the machines ever need to be manually patched. We also scan our subnet daily for vulnerable machines and proactively patch any machines that turn up that way. Personal laptops were a problem (briefly) but after an incident at another location where the offfending user was terminated folks have gotten the message that it is not OK to attach non company owned computers to the network.

    1. Re:We use a similar concept @ work by kryptkpr · · Score: 4, Insightful

      zero infections with no anti-virus suite running on the machine at all.

      And how exactly do you know there have been zero infections.. without a virus scanner? Or is the machine not connected to the 'net?

      --
      DJ kRYPT's Free MP3s!
  11. Reduces the value of spam spewing owned boxen by G4from128k · · Score: 3, Insightful

    Technology such as this reduces the value of virus-created owned boxes. The creators of viruses that want to create spam-spewing machines would find their spam spewer useless. During the infection phase, the virus-spreading emails would get the infected box tagged and blocked. During the usage phase, the virus-creator/spam sender would find that the owned box is useless because all the messages get blocked.

    This tech does not preclude malaciously-motivated viruses, but it does reduce the profit potential of creating spam networks.

    --
    Two wrongs don't make a right, but three lefts do.
  12. Spamhaus by AndyFewt · · Score: 5, Insightful

    Didn't Spamhaus recently launch the pretty much the same service called the XBL?

    "The Spamhaus Exploits Block List (XBL) is a realtime database of IP addresses of illegal 3rd party exploits, including open proxies (HTTP, socks, AnalogX, wingate, etc), worms/viruses with built-in spam engines, and other types of trojan-horse exploits." -- http://www.spamhaus.org/xbl/index.lasso

    The only thing I thought was weird about the Dutch system was: "An IP address gets listed after receiving at least 2 viruses".. I think that may be a typo as the system scans some email and grabs the ip from the headers if a virus/worm/trojan is found. But if it's not a typo, any email address that receives 2 viruses it gets listed (regardless of infection) is a pretty sucky system.

  13. Translation for non-Dutchies by mrjb · · Score: 4, Informative

    Chello en Tiscali top-spreaders of viruses
    A database with infected pc's is the foundation of an ambitions project that should reduce the flood of virus emails
    A number of Dutch providers is currently testing a worm blocker based on an extensive database of infected pc's. This file has been kept up-to-date since 2 weeks ago by BIT, a provider for businesses. In this database, amongst other things, is visible from which IP address which virus is being spread.

    Other providers can use this database to inform their own customers that their computer is infected and bothering other people, explains Alex Bik of BIT. Self-propagating viruses (worms) are causing more and more trouble, both to private users and providers.

    BIT itself has been using the automatic blacklist-system since last week, to protect their customers against the ever growing stream of virus mails. By now, a large number of Dutch [internet] providers, including XS4ALL, Zonnet and IS Internet Services, also have access to the data.

    Port 25

    In its database, BIT keeps track from which IP addresses virus mails are sent. This sending [of emails] often takes place directly via port 25 from infected computers. As soon as more than 2 infected emails arrive at BIT within 25 hours, the IP address is blacklisted for 24 hours. However, the ip-addresses of mail servers of known providers are not added to the database.

    Chello tops the list

    The list shows that other providers, too, can benefit from the blacklist. Customers of Chello, Tiscali and @home top the list of major virus spreaders (over 1000 virus emails). The topper is an ip-address at Tiscali, from which as much as 12000 sober G-mails have been sent.

    In total, Chello leads with over 27000 sent virus mails with the 25 main 'spreaders', followed by Tiscali (almost 23000), @home (almost 20000), Wanadoo (over 14000), HCCnet (almost 13000) and Planet [internet] (almost 12000).

    --
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  14. Tech support by Fullmetal+Edward · · Score: 3, Insightful

    "I can't send a file to my friend or even get to some website, whats wrong with my PC?"

    "You been virusing people, sending spam and being a git."

    "No I haven't..."

    I don't want to be that tech support guy because this is will happen and often.

    --
    --- [Insert intresting Sig here]
  15. other alternatives to stopping worms by angryLNX · · Score: 3, Interesting

    I have been doing a high school science research class project on stopping the spreading of internet-borne worms though analysis of epidemic models and such. I have come across many different methods for stopping the distribution of vulnerability-based worms, so I'll share here (in order from most innovative to most obvious): First, a very ingenious method coming from Dartmouth's Institute for Security Technology Studies. They propose a method called monitoring the internet for plumes of ICMP unreachable messages. Software is installed on routers which records the ICMP unreachable messages being sent and sends data every once in a while to a central server which analyzes the data and sees which things are probably random-scanning worms. This is probably the best idea I've seen yet, but most likely the hardest to implement (as router software is usually tried to keep air-tight). The bad ports and such would then be filtered or turned off as appropriate. A second method which may have been talked about on here or not is "good" worms. Worms which sit around and listen for worm data would then send a copy of itself from the computer which was scanning them, therefore fixing another hole and having that computer be another "good" computer. The bad thing with this is that it will only really work when the worm is at its peak, when damage has already been done. It would be useful for cleanup, but of course there are issues with privacy and control would be rampant. Another "solution" is getting users to install firewalls and anti-virus software but thats a more obvious and hard to implement solution. I am modeling all of these possibilities using a mathematical model for epidemics, and seeing where which one would theoretically be most useful and such, and I'll take a look at the method used in the article.

  16. dynamic IP addresses by curator_thew · · Score: 3, Insightful


    Sorry to hear if you're on a dynamic IP address: be prepared for intermittent connectivity to peers in said networks running this technology.

    I don't think this is a good solution, anyway. The better solution is for ISP's to use SNORT or something else to real-time detect _outgoing_ viruses and worms from their own customers, and in response, send email to the customer warning them.

    This has a number of benefits: i.e. it actively works towards the source of the problem, not just "blocking" the problem out.

  17. Problems? by gmuslera · · Score: 3, Insightful
    • There are worms that don't have their own smtp engine. Ok, big mail servers are whitelisted, but what about small/medium mail servers? blocking entire mail servers because a single user of it is infected?
    • Modems/Dynamic IPs: an infected user uses an IP, gets blocked, and disconnects/gets another IP. The probably clean user that gets now the old IP gets also blocked. With enough ip rotation and certain percent of infected users you could end blocking entire ISPs (ok, the banning is only for 24 hours, but my ip rotation is every 12 hours, so i will surely hate if i can't do something if some clueless idiot got infected and blocked)
    • IP grouping: At least here internet cafes normally have one public IP for all computers, and that happens too even with companies with their entire traffic masqueraded thru one IP. If one gets infected (and eventually cleaned) the entire place is blocked
  18. We're doing something similar by bigberk · · Score: 3, Informative
    So, does anyone have useful remarks on why this may succeed or fail?
    The WPBL is a very similar effort, using distributed spam sightings to block IPs. We focus on spam, while virbl specializes in viruses. I think they'll have good success provided their method of virus detection is very accurate. In our case, statistical bayesian-like filters help us get accurate spam sightings.