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Botnet Crime Security IT

New ZeuS Botnet No Longer Needs Central Command Servers 137

Posted by timothy
from the andromeda-strain dept.
c0mpliant writes "Researchers at Symantec have identified a new variant of the ZeuS botnet which no longer requires a Command and Control server. The new variant uses a P2P system, which means that each bot acts like a C&C server, but none of them really are. The effect of which is that takedowns of such a network will be extremely difficult because there is no one central source to attack."
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New ZeuS Botnet No Longer Needs Central Command Servers

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  • by jonamous++ (1687704) on Saturday February 25, 2012 @10:12AM (#39158259)
    What if the commands need to be signed?
  • by Anonymous Coward on Saturday February 25, 2012 @10:24AM (#39158319)

    Insecure is relative. Computers and systems have the same problems as the security of a country. You are calling for a TSA like approach for software and systems. The only 100% secure device is one with no human interface device, no ports to allow new data (no net, USB, CD-rom, etc.) and maybe not even a power cord.

    The most popular systems will have the most viruses written for them. Look at Windows. Now look at the reports of Apple OS viruses popping up as that system was becoming more popular. If everyone surged to Linux there would be a surge of viruses there too.

    Then you get into the operators. Not everyone can be trained to be 100% knowledgeable in every up or downside on the net. The only system that would work is some type of licensing like with cars. Oh wait, we have idiots who talk, text, eat, put make up on, drive drunk, and all that already with that program.

    Then you run the risk of having only official and approved operating systems. And FDA of sorts for computer systems...

    *pauses* Are you trolling? I mean, you are effectively asking for a series of laws that would not just put us on the road to a "Right to Read" future, but hang up the street signs and lighting as well.

  • by Kjella (173770) on Saturday February 25, 2012 @10:29AM (#39158355) Homepage

    You're still thinking in terms of a C&C, when it doesn't apply anymore. Think of it more like a contagion, there's no "C&C" humans only people in contact with other people in contact with yet more people. There is no command to become a C&C. Commands are encrypted but also signed by the operators and nodes only have the public key to that so you can't fake one. They can just introduce a command anywhere, to any node and it'll relay it to its peers, that'll relay it to it's peers again amd so on until everyone got the command. You probably use a unique ID to avoid loops, like command 0xfe36735b I've already relayed, no need to relay it again.

  • by Wierdy1024 (902573) on Saturday February 25, 2012 @10:53AM (#39158459)

    I'm not sure about your comments re: keys.

    It seems relatively easy to design a botnet to be peer to peer and yet not able to be taken over by a rogue node. Consider a P2P overlay network where each node plays "chineese whispers" and forwards any packet to all neighbours (with some TTL limit).

    The botnet owner creates a public private keypair, and uses his private key to sign control messages. Each host takes each incoming packet and checks if it is signed by the botnet-owner, which requires the public key of the botnet owner, and is built into the code. If someone reverse engineers a node, all they have is the public key, so can't sign messages (since signing requires a private key).

    An attacker could still DoS this network with unsigned Control messages, but that can easily be thwarted by:
    a) never forward any unsigned message
    b) forward signed messages only if it's version number is higher than the last forwarded message.

    To hide himself and operate the network, the botnet owner can use TOR or some other anonymising service to connect randomly to any node in the network (rather like utorrent DHT does), and send a signed control message with a version number higher than any seen before by the network.

  • by irtza (893217) on Saturday February 25, 2012 @11:00AM (#39158491) Homepage

    There is no need for a private key for the signature nor the need for a signature authority. If I were to give you a public key and I sent you a signed message, you could verify the message came from me as long as my private key was hidden from a third party.

    This setup still requries C&C software, but as long as the C&C software is not distributed, each node can not initiate a command, but can propogate an already signed one. There would need to be a program that can insert a new signed command, but that need not be on every node. It would be much like gnutella - maintain a list of nodes to connect to and if you get in, you isue your command - disconnect from the network and you can reconnect at will from another IP address.

  • *yawn* (Score:5, Insightful)

    by Tom (822) on Saturday February 25, 2012 @11:24AM (#39158589) Homepage Journal

    This comes as a surprise to anyone? Really? I attended conferences almost 10 years ago listening to and giving speeches about stuff like this. The technology is trivial, the only reason the bad guys haven't moved to the hardened networks stuff yet is because there simply was no need.

    If you want to know what's next, I can dig out my old slides. A guy from Britain and I came up with several highly resistant network designs. I think our final one would remain largely intact if you took out 90% of its nodes.

    Like all things in fighting spam and large-scale scams, eliminating the C&C servers was one step that was useful for a short span in time. There are still old botnets out there that you can take out with this approach, but the more advanced ones have left that window of opportunity now.

    As long as our politicians refuse to tackle the fundamental problem - that of tiny crimes in massive quantities - we're stuck. Our legal system still works by "cases", adapted to a physical world where the crime has an easily enumerated set of victims, each of which having suffered considerable damage. The legal and political systems still don't understand both the tiny and massive scales they need to deal with in a virtual world. Scam 10 people out of $1000 each and you'll get a court case and jail time. Scam 1,000,000 people out of a cent each and nobody in law enforcement will care, even though the damage to society is the same.

  • by Anonymous Coward on Saturday February 25, 2012 @11:40AM (#39158731)

    Popularity only means attractive target. Vulnerable is not related to popular except that it also makes the target more attractive.

    The gold in Fort Knox is attractive. However, the security of Fort Knox is so unattractive that it offsets the attraction the gold has to would be thieves. The result? Crooks knock off small banks instead. The money is only attractive if it's reasonably easy enough to get.

    Microsoft's market share on the desktop has not changed in a significant way. Yet, most agree that Windows has become more secure despite the fact that we've been told by idiots like you that it was impossible because of their market share lead.

    Installing AV and security products doesn't effect OS market share either but most agree that it improves security. Again, market share is just a small part of of the equation.

    Adobe's Flash and PDF viewer were very widely deployed and have never been secure, ever. They were largely ignored up until Microsoft started making their browser and OS more secure. At that point we saw malware shift to Adobe products. They didn't suddenly become more popular back at the end of 2009 when researchers projected Flash and Reader the new attack vector of choice. The MS vulnerability well was drying up. It wasn't a shift in market share. It was a shift in security. MS got some and Adobe didn't.

    Considering the rapid growth of Chrome, why aren't security researchers saying it's the next big attack vector? It certainly has experienced a "surge" in popularity.

  • by Anonymous Coward on Sunday February 26, 2012 @03:17AM (#39162623)

    If the signatures need to be verified by a signature authority controlled by the attackers

    Red Flag 1: You don't know how Public Key Cryptography works.

    There is nothing magical about Certificate Authorities like Verisign. All they do is generate a random N-bit public/private key pair that meets certain mathematical rules (must be prime) then stick it inside a certificate (X.509 standard) then sign that certificate using the Verisign private key. How do people know what the Verisign public key is? The key is built-in to Windows, Firefox, Chrome, etc. All these programs have nothing more than a
    const unsigned char verisign_public_key[] = { /* key bytes */ };
    (Exact format differs, usually Verisign's self-signed X.509 will be stored in the out-of-the-box key store but there's nothing magical about that)

    Otherwise, the commands must be self-signed, so an ordinary man-in-the-middle attack on any one the nodes could reveal the signature to you.

    Red Flag 2: You don't know how cryptographically secure communication protocols work.

    You've clearly picked up some vague knowledge about SSL/TLS and have bluntly assumed that every encrypted protocol works the same way. Hint: They don't. The command protocol in question is most likely going to function like (if not actually is) SSH, if you have the public key stored locally (See verisign key above) inside the botnet software and you have the private key on the C&C system so that it never touches the network then there is no MITM possibility. Hell, you don't even need to encrypt really, just signing is good enough.

    MITMs exist because SSL sends the public key across the network from the server, if someone intercepts the key transfer then they can insert their own key instead. If the key isn't sent then it can't be intercepted (see laws of physics), there is nothing magical about it.

    But I have never done anything like that before, it is probably much more difficult than I am making it sound.

    As the other AC said, if you don't know anything about the relevant field then don't try to speak as though you have any sort of authority. Buy yourself a copy of Bruce Schneier's 'Applied Cryptography' before you try to do anything related to cryptography in future, it'll save you and your users from a world of hurt.

It's not so hard to lift yourself by your bootstraps once you're off the ground. -- Daniel B. Luten

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