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Hiding Packets in VoIP Chat

Posted by CmdrTaco on from the because-you-can dept.

holy_calamity writes "Two Polish researchers say they have developed a system to hide secret steganographic messages in the packets of a VOIP connection. It exploits the fact that VoIP uses UDP, not TCP; it is designed to tolerate some packets going missing -- so hijacking a few to transmit a hidden message is not a problem." You may also be interested in reading the original paper.

3 of 90 comments (clear)

  1. UDP Only... by mchawi · · Score: 4, Interesting

    Based on the RFCs for VOIP they are supposed to support UDP and TCP per the new specs. Most companies are moving to support both so you can choose, but some of the large companies are going to TCP because this is what all of the 'Unified Communications' packages go with (such as Microsoft Office/Live/Communicator, etc).

    One of the reasons they are leaning this way is security. Go figure.

    Besides that, I don't really see the point. What does this solve that just encrypting sensitive data wouldn't?

    1. Re:UDP Only... by zappepcs · · Score: 4, Interesting

      Well, it might ensure that the NSA et al are not infecting your VoIP equipment with tracing software while you are talking, and those pesky terrorists might not be able to send text data about the next planes to hijack while having a bad conversation quality exchange about prayer times and how to find Mecca while in Chicago.

      When a security hole is found, it needs to be plugged because the threats it poses are not always explicitly understood at first glance.

      In fact, in computing in general, there are multiple ways to sneak a couple of packets through here and there if you're willing to be patient. I'd mention a few of them, but that would probably get me on a fucked up watch list. The fact remains that this is but one way to do so. Monitoring the network packet for packet won't uncover them all either, nor will it out any terrorists who don't want anyone watching their communications. Why, even my music on hold can contain data for transmission to the right person with the right audio equipment. Never mind a blog post, or email. In fact... woooootttt! I could use the NSA's website as the key for an encryption routine that they would never decode in several decades of trying. sigh, but that won't stop them from telling us that it's all for our protection.

      Just encrypting it would not stop the possibility of rogue data if your application can withstand a few missing packets. VoIP is not the only protocol which is susceptible.

      --
      Support NYCountryLawyer RIAA vs People
  2. Re:Well... by h4ck7h3p14n37 · · Score: 5, Interesting

    That reminds me of a neat story.

    A few years ago at a tech conference I met someone who worked for the data storage division at Dell. Some of the technical manuals that the engineer needed for their work were classified as secret (product hadn't gone to market yet) and the engineer had to sign various NDAs with the company to get access to the documents.

    Said engineer compared their copy of a manual with another engineer's copy and discovered that each manual had a different set of spelling errors. Apparently Dell was generating documents with unique sets of typos in order to be able to track down the identify of the person who leaked a document.