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Security Flaws Allow Wiretaps to be Evaded

Posted by samzenpus on from the it's-coming-from-inside-the-house dept.

An anonymous reader writes "The New York Times is reporting that a team of researchers led by Matt Blaze has discovered that technology used for decades by law enforcement agents to wiretap telephones has a security flaw that allows the person being wiretapped to stop the recorder remotely. It is also possible to falsify the numbers dialed. The flaws are detailed in a paper being published by the IEEE. Someone who thinks he's being wiretapped can apparently just send a low tone down the line that turns off the recorder. The link has a demo."

18 of 191 comments (clear)

  1. Is this is a big deal? by matr0x_x · · Score: 2, Insightful

    How serious is this though - I mean, if I knew my line was tapped instead of working on getting it untapped I'd simply work on getting a second line!

    --
    LINUX ONLINE POKER: Linux Poker
    1. Re:Is this is a big deal? by ndansmith · · Score: 4, Insightful

      Likely the powers-that-be would know about your new line and tap it as well. It is better to let them think they are tapping you, when in reality you are circumventing the system.

    2. Re:Is this is a big deal? by Anonymous Coward · · Score: 3, Insightful

      Surely if sending a low frequency tone becomes a "standard", law enforcement agencies will change their methods to so that wiretaps can't be blocked by a low tone? In fact, the aticle says that only 10% of 'dated' wiretap machines can be defeated in this manner anyway, so don't rush out to buy the next phone offering compl33t an0nym1ty from the fedz!

      Where's the big deal?

    3. Re:Is this is a big deal? by tomhudson · · Score: 5, Insightful

      Do you want the truth?

      You can't handle the truth!

      " Look, our disinformation campaign is working! People who have something to hide will send the recorder activation tone down the line before each call, thinking they're keeping us from listening in. Bwhaahahaha"

      The truth is that in the current environment, you can't trust anything. Use your PC to scramble the call. If its that sensitive, anything else is foolish. Or use a one-time pad to encode it.

      Think of it, if you were the "powers that be", isn't this how you'd do it?

  2. In other news... by ThatGeek · · Score: 5, Insightful

    In other news, smart people can avoid being caught by doing stuff...

    I mean, any dolt can PGP or GnuPG encrypt a message or just hand deliver messages. Things like wiretaps are good for the duller knives in the drawer. We should still use them to "grab the low hanging fruit" and look elsewhere to capture the rest.

    If a person knows he's being wire tapped, he won't say anything incriminating anyway, and if the feds/cops don't get what they want over the phone, they'll just bug some offices instead.

    --
    What are you eating? isItVeg?.
    1. Re:In other news... by PlayfullyClever · · Score: 5, Insightful

      Or just use a pre paid cell phone.

      The only groups these wiretaps hurt are the law-abiding citizens. The smart (read: dangerous) criminals have it all figured out-- Prepaid cell phones.

      Pre-paid cell phones are literally disposable, one-use toys to the bad guys. You don't even need a fake ID, just cash, and not all that much at that. How can they tap your phone when you use a different phone for each call? The best they could do is tap all the pre-paid phones and listen to every conversation out there -- good luck with that! (wanna bet the NSA is big into voice recognition?)

      --
      Check out my website: Playfully Clever
    2. Re:In other news... by s20451 · · Score: 2, Insightful

      The corollary to your post (and the counter-argument to the grandparent) is that a person planning nefarious acts should send everything in plaintext.

      Sending encrypted e-mails, for example, when nobody else in the world is doing so, is like putting a huge sign on your front lawn saying, "INTRIGUING SECRETS ARE GOING ON IN HERE!".

      Remember that cryptography is only one link in the information security chain, and that everything has to get back to plaintext eventually. Once the feds are interested in your data, there is nothing stopping them from parking a truck across the street and harvesting your info using TEMPEST.

      --
      Toronto-area transit rider? Rate your ride.
    3. Re:In other news... by darkmeridian · · Score: 2, Insightful

      Yep. It's not as though the exploit allows the cops to think nothing's wrong. Surely, the cops will be curious when their wiretaps go:

      Caller: Yo. It's me.
      >CARRIER LOST

      Furthermore, the FBI has insane bugging technologies. Forget wiretaps. If they really want to get you, they'll stick parabolic or laser mikes all around you. Or bug your car and office or simply follow you around and take pictures of all your friends who they then bug and wiretap. Or what they really do is catch an associate on a felony and extort^H^H^H^H^H^H convince them to turn state's witness.

      So while cool, this exploit probably does not help "bad" guys too much.

      --
      A NYC lawyer blogs. http://www.chuangblog.com/
  3. Feature, not a bug... by Anonymous Coward · · Score: 3, Insightful

    That way when the party officials want to do something underhanded, they use the red 'bat phone' that nukes any cops that are trying to listen in on them. In this way, they can have it both ways. Watch the proles without being watched themselves.

  4. RTFA and all that by kebes · · Score: 5, Insightful

    Let's keep this in perspective. The article says:

    A spokeswoman for the F.B.I. said "we're aware of the possibility" that older wiretap systems may be foiled through the techniques described in the paper. Catherine Milhoan, the spokeswoman, said after consulting with bureau wiretap experts that the vulnerability existed in only about 10 percent of state and federal wiretaps today. (emphasis added)

    So basically it is a minority of antiquated equipment that is vulnerable. Moreover, the person being wiretapped probably doesn't know what system is being used. It is not going to be possible to know, with any assurance, that you have actually defeated the system.

    What this probably means is that the FBI will phase out these older systems a little faster than they intended to (mostly due to the publicity-- they were probably already aware of this vulnerability, but didn't care much because "the bad guys" were not aware of it).

  5. In other news... by Psionicist · · Score: 4, Insightful

    In other news: A team of researchers belived to be linked to an unknown group of terrorists was charged under the DMCA and PATRIOT act as a threat to national security. They are now being held for an unknown period if time, awaiting trial...

  6. Don't use in-band signalling/control by AcidPenguin9873 · · Score: 2, Insightful

    Engineers figured this out a long time ago. TFA says it's only 10% of current systems anyway.

  7. Double-edged sword by jemenake · · Score: 3, Insightful
    Someone who thinks he's being wiretapped can apparently just send a low tone down the line that turns off the recorder
    Of course nobody would actually play that tone over the phone unless they were trying to foil wiretaps, right? How long do you think it'll be before the feds try to ammend the Patriot Act to allow them to listen just for that tone even on lines that they don't have a wiretap warrant for? Imagine picking up any phone in the U.S., playing the tone into it, and immediately getting your conversation recorded.... simply by virtue that you've already demonstrated your "guilty mind".

    I feel safer already....
    1. Re:Double-edged sword by PlusFiveTroll · · Score: 2, Insightful

      Actually that sounds like a good idea, now the feds will have 30,000 hours of geeks talking about upgrading linux on there new athlon. The .gov will spend millions trying to go through all the tapes, most calls will never be listened to. All of the sudden the 'real' terrorist they should have been listening to in the first place will blow something up.

      Moral of the story, dont waste your time with a person just because they want a little privacy.

  8. Limited Value by digitalchinky · · Score: 3, Insightful

    *Ahem* From the 'wire tapping' I know of it's all man in the middle, digitised, and stored on hard disk - with the cooperation of the telecoms or without. I haven't seen a 'tape recorder' in a good 10 years now. Still have them, just not needed any longer. I should imagine, given the hardware used in Australia, that US police would do a similar thing and if not - identical. The likelyhood these days of a machine that could be switched off remotely I would suggest is improbable at best.

    They did use "publicly available information" - what is made (or leaked to the) public is often years out of date, inaccurate, or simply not even true - rarely does it describe the technology in actual use, so don't go and loosen the straps on the tin foil just yet :-)

  9. Who ya gonna call? by Chris+Tyler · · Score: 2, Insightful

    Sure, prepaid cellphones can be counted as "disposable, one-use toys", but you have to have someone to call! If both parties are going through prepaids like candy - one or two calls then on to the next phone - managing the constantly-changing phone numbers becomes more than a small chore, and it becomes a nightmare to keep a half-dozen parties in touch with each other. It's not going to happen on both ends of the connection.

    You don't need to tap the prepaids, you just need to tap the numbers that the prepaids are calling.

  10. Re:But sometimes... by Anonymous Coward · · Score: 2, Insightful

    somebody, presumably a beancounter at one of the telecoms, decided to bill the customers in question for this 'service'.

    Smart move if you can get away with it.

    LI (lawful intercept) costs many millions every year. The general trend (amongst the larger police states at least) has been to "mitigate" this cost by simply legislating that the carriers must provide these services and must provide them at no cost to the requestor. This leaves the carriers eating a great whacking cost for the privilege being thrown between the government and the rest of the criminals. In most countries I expect this charge is part of the "system access fee" or hidden in the 911 charge. Perhaps Germany neglected to do this and was none-too-gently reminded that somebody has to pay the piper.

  11. Re:I, for one, welcome security flaws by harryseldon · · Score: 2, Insightful

    I own a publicly traded company.

    You here demonstrate you have no idea what a publicly traded company actually is.