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Security Software

The Rising Barcode Security Threat 125

eldavojohn writes "As more and more businesses become dependent on barcodes, people are pointing out common problems involving the security of one- or two-dimensional barcode software. You might scoff at this as a highly unlikely hacking platform but from the article, 'FX tested the access system of an automatically operated DVD hire shop near his home. This actually demanded a biometric check as well, but he simply refused it. There remained a membership card with barcode, membership number and PIN. After studying the significance of the bar sequences and the linear digit combinations underneath, FX managed to obtain DVDs that other clients had already paid for, but had not yet taken away. Automated attacks on systems were also possible, he claimed. But you had to remember not to use your own membership number.' The article also points out that boarding passes work on this basis — with something like GNU Barcode software and a template of printed out tickets, one might be able to take some nice vacations."
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The Rising Barcode Security Threat

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  • by MiniMike ( 234881 ) on Monday December 31, 2007 @06:26PM (#21870786)
    > The article also points out that boarding passes work on this basis -- with something
    > like GNU Barcode software and a template of printed out tickets, one might be able
    > to take some nice vacations."

    Yeah, in Guantanamo...
    • by jacquesm ( 154384 ) <j&ww,com> on Monday December 31, 2007 @06:30PM (#21870816) Homepage
      water boarding passes ?
    • Re:Nice vacations? (Score:5, Interesting)

      by Penguinisto ( 415985 ) on Monday December 31, 2007 @06:31PM (#21870822) Journal
      There's also the missing component of having the corresponding data in the airline's computer network/system that matches the barcode for that flight, at that time, on that date, at that gate, for that seat, etc etc... it only get more complex if you're dumb enough to try and check baggage as well.

      You'd have to study more than just algorithms to get on a plane - all of the data the barcode represents would have to be in the airline's computer as well, else you won't ever get past the gate.

      Unless there's some sort of secret code that gives free flights (could be, like for stewardesses returning home and such), it just ain't gonna happen that way.

      Of course you could get real lucky, but it would have to be something on the scale of winning enough money via the Lottery to pay for the flight.

      /P

      • Re:Nice vacations? (Score:5, Insightful)

        by JacksBrokenCode ( 921041 ) on Monday December 31, 2007 @07:50PM (#21871240)

        You'd have to study more than just algorithms to get on a plane - all of the data the barcode represents would have to be in the airline's computer as well, else you won't ever get past the gate.

        Ticket numbers are tied to specific passengers, not just flight & seat info. If you got to the point where you could accurately predict future ticket numbers for other passengers, you'd be able to get past security and likely on the plane... until a legitimate passenger shows up with the same ticket number. Even if you didn't sit in the seat you forged, they'd force everyone to disembark and reauthenticate themselves with photo-ids. Then there's the uncomfortable situation of trying to explain why you forged a boarding pass to circumvent security measures.

      • I don't think that's the mechanism for this attack at all. You'd take the fake barcodes to the e-ticket terminals and pretend to be someone flying that day. Then you just take their tickets. Of course, when they do arrive and make a fuss, you'll get flagged and caught when you try to use the tickets at the gate.
        • ... I am Korben Dallas
        • The example in the article was not that you fly as the other person, but that you check baggage in their name. Perhaps containing drugs to be smuggled or a bomb.
          • Which is why Boeing will turn out to have been surprisingly prescient in not building an A380 competitor. The future of air travel is smaller, more numerous, more direct flights, (which happen to be less threatening to buildings as a bonus) as evidenced by the fact that Southwest regularly posts profit, while Delta does not.
      • by Anonymous Coward on Monday December 31, 2007 @08:56PM (#21871560)
        I've done this for kicks just to see if I could do it, but once I brought one of my fake ID's and fake boarding passes to the airport and got through the "security" (security? BAHAHAHA!) and made it into the terminal. Bought some drinks, ate some food and went home.

        No one was the wiser.

        You see, it's just a billion dollar FARCE and a WASTE OF TAXPAYERS MONEY for the *feeling* of safety when there really isn't any.

        Of course I couldn't get on the plane. I couldn't get on a plane in 2001 without a correct ticket anyways. They had the barcode scanners to "check" you into the plane anyhow. At least, I remember them being available back in 1999 -AND- I wasn't too keene on getting onto a plane where there weren't enough seats where I'd get caught :P

        Anyways, just as I said, this is easy to blow a hole through. There's nothing in the world that makes me more mad than being patted down, scanned or searched before boarding PUBLIC TRANSIT. I'm not a criminal, wtf are government agencies doing there?

        (posted anon and through a couple anon proxies)
        • Ya, big man (Score:1, Interesting)

          by ebvwfbw ( 864834 )

          You see, it's just a billion dollar FARCE and a WASTE OF TAXPAYERS MONEY for the *feeling* of safety when there really isn't any.

          (posted anon and through a couple anon proxies)

          Mighty tough behind proxies. If it is such a farce (as if you know what a farce is that is, get a dictionary), why not post it from your account? As for it being a waste of money which is what I think you are trying to say, who would have bet even a dime that there wouldn't be another terrorist attack in the next 4 years after 9/11

        • by afabbro ( 33948 )
          (posted anon and through a couple anon proxies)

          Lamest. Post. Ever.

        • by D3 ( 31029 )
          This is most certainly NOT a PUBLIC TRANSPORTATION system. The individual carriers are private businesses and you are contracting them to transport you under license from the FAA. You have no reasonable expectation of not being screened before boarding. If you don't like it you have the option of other travel (car, boat, etc.), the option of getting your own pilot license and plane, or the option of hiring a chartered flight.
        • by pnutjam ( 523990 )
          One morning I was watching the news and they had TSA agents searching people before they got on the city busses, to "remind people busses are under the authority of the TSA". It was total bullshit, especially since they only searched people at a couple stops.

          In hindsight I suppose they probably had a tip and were looking for someone specific.
          • One morning I was watching the news and they had TSA agents searching people before they got on the city busses, to "remind people busses are under the authority of the TSA". It was total bullshit, especially since they only searched people at a couple stops.
            In hindsight I suppose they probably had a tip and were looking for someone specific.

            Nope, all they were doing was cracking the whip to make sure that the sheeple remember that the whip is there, and to keep the old "line up against the nearest wall, lo

        • made it into the terminal. Bought some drinks, ate some food and went home.
          I've always wanted to do that: take advantage of the awesome, yet inexpensive, bars and restaurants that can only be found in airports.
        • by rtechie ( 244489 )
          I've never done this, but what the anon poster is describing is easy because they DO NOT SCAN the boarding passes at security. Most boarding passes are now single-page printouts printed AT HOME by the passenger. All you have to do is mock up a fake boarding pass in Word or something with information that matches your fake ID and you're done. You can walk right through airport security. You can't get on a plane with that fake boarding pass, so you'd have to steal someone else's boarding pass and put THEIR ba
      • by ejecta ( 1167015 )
        The secret code is: Hug the landing gear. Remember to wear a parka, it gets a bit fresh up there.
        • by mpe ( 36238 )
          The secret code is: Hug the landing gear. Remember to wear a parka, it gets a bit fresh up there.

          Apparently being a Russian teenager can help too.
      • by KWTm ( 808824 ) on Monday December 31, 2007 @09:21PM (#21871680) Journal

        There's also the missing component of having the corresponding data in the airline's computer network/system that matches the barcode for that flight, at that time, on that date, at that gate ...
        You won't be so sure after you hear what happened to me.

        Once, I got on a flight to Hawaii. The plane was about to push off and, like most of the other passengers, I had settled into my seat. Then some other passenger came and said I was sitting in her seat! We compared boarding passes, and lo and behold, both of our passes were for the same seat! We couldn't figure it out, so we asked the flight attendant for assistance. She couldn't figure it out either, so she had to go back to the boarding gate with our passes to ask the ground crew to figure it out.

        After a while, someone finally realized what happened. I was on the wrong flight! I was on board a direct flight to Hawaii, but I had actually bought a ticket to fly to San Francisco and from there transfer to a flight to Hawaii. I had always thought of it as "my flight to Hawaii" and had completely forgotten that I would have to transfer. The boarding gate was off by one, but the airport always changes boarding gates at the last minute and I figured this was one of the times. And the flight was scheduled 5 minutes before my actual flight, so I figured that the flight was early. I lined up like everyone else with my Internet-printed boarding pass, the computer scanned it, and I got on board just like everyone else. There was no alarm that I was on the wrong flight or anything like that.

        That was with me accidentally getting on the wrong flight. What do you suppose could happen if someone was intentionally trying to pull off a deception? The only redeeming feature is that this happened in 2002, and I hope that airline security has improved somewhat since then. (I can dream, can't I?)
        • Hmm. I boarded a flight on Dec. 24, sitting in seat 27C. As I got on the plane and handed the ticked to the member of cabin crew (having already had this boarding pass scanned at least twice) for her to direct me to my seat, she pointed it to me, and then did a double take.

          "Sorry," she said, "I thought your ticked was for December 27, not row 27."

          Now, either she was tired, or that's something that happens sometimes. Anybody know?
        • by jbengt ( 874751 ) on Monday December 31, 2007 @10:35PM (#21871994)

          "and I hope that airline security has improved somewhat since then. (I can dream, can't I?)"

          Keep dreaming.
          My experience with a current construction project for a major airline at a major airport speaks to a discomfortingly confused security situation.

          The first time I went to the site with the Architect, who had a badge to escort us into the terminal, we were refused entry at 3 different points, always told to go somewhere else that wouldn't let us in. Then we went to an airline official, who said that the badge the architect had would get us in at a security gate that we tried before, so she escorted us there, and we weren't let in. So she did about a half hour of research, and found that we needed to go to the desk where they check in pets in their crates! There they checked the architect's badge and our IDs and issued us each a ticket-like piece of paper that we took to the security gate. There they took that "ticket" from us (and my co-worker's zippo lighter) and let us through. We then had the run of the place, without any ticket or pass.
          We spent over an hour and a half getting in to do 2 hours of work. Then, after suffering through all that security red tape, we at one point got separated from the contractor with the keys, while we were in the non-secure loading dock (accessible from a public roadway). But not to worry, a friendly worker let us back to the secured passenger terminal side.

          The second time I went with my boss, who picked up his own badge that he applied for three weeks earlier. He had been told it was ready to pick up. It took a little over an hour wating in lines and watching safety videos to pick up the badge. But when we tried it (it was a swipe and pin number type), it didn't work. So we went back down to the security badging office, only to find a sign on the door saying that they were closed for lunch and would be back at 1:00pm (even though it wasn't noon yet). I went back to the office, and he stayed the rest of the day to get it straightened out and do about an hour of work.

          The third time I went, construction was well under way, the walls were knocked down, and the only thing bewteen the public parking and the secure air side was some pastic sheeting.

          Did I mention that both the existing layout and the new design include a loading dock that connects the non-secured public roadways with the secure airside through a locked, but un-manned, door? Anyone on the inside (including employees, or sneaky passengers) could open the door, (or man the freight elevator if they had the key), and bring large, explosive things off the truck with a forklift and into the passenger terminal.

          • by mcrbids ( 148650 )
            I have no doubt that temporary security issues exist. The hard part is turning these temporary situations into real, exploitable, predictable vulnerabilities.

            I'm a private pilot. I walk into the local FBO (like an airport terminal, but for private planes) and after a very brief check, I'm able to freely roam the "secure" side of the airport. Not just where the "small" planes are, the whole "other side" of the airport. I can drive a truck out to the plane I'm flying, without any check whatsoever of the truc
            • by jbengt ( 874751 )

              In short, it's the random nature of security enforcement that makes it effective, not the universal enforcement.
              I agree
              In my expereince they are very good at that randomness, the rules seem to change arbitrarily every week, if not by the day.
              But it's very frustrating when you're just doing your job, and the doesn't-seem-so-secure security doubles the costs of doing it.
            • Next time you take off your shoes, remember this tidbit of wisdom: 9/11 might have been prevented if we had then today's general paranoia, but the specific measures out there today would not have stopped it. Today's meaures, if effective from 9/1/2001 forward would not specifically have prevented the horrible attacks on 9/11/2001.

              Perhaps I'm misunderstanding you, but wouldn't securing the cockpit doors have prevented the hijackings that took place on 9/11/2001?

          • by tarpy ( 447542 )

            My experience with a current construction project for a major airline at a major airport speaks to a discomfortingly confused security situation.
            Oooh, ooh, let me guess...my guess would be that this is about the Terminal 3 rehab American is currently doing at O'Hare.

            Not only does this story sound like stupid aviation red-tape, but it's also got some classic Chicago moments (the badging office being closed until 1 pm is a pretty good give-away).
          • Reminds me of a warehouse I had a temporary job in. We temps had no badge to get in, but we couldn't leave the door open, even temporarily, for the sake of perceived "security".

            Never mind that the bay doors (where the trucks dock) were wide open.

        • > That was with me accidentally getting on the wrong flight.

          A similar story happened on a flight from France to Germany in the nineties. Because of overbooking I had been upgraded to business class and no one else claimed the seat, so I was completely unaware of being on the wrong flight. Only during the traditional hostess announcement after take-off did I mention to my neighbor that the wrong destination was announced... Lufthansa nicely took it as their own error and re-routed me on a flight from Stut
      • Re: (Score:1, Interesting)

        by Anonymous Coward
        Keep in mind that there are non-evil reasons someone would want to get past security and out on to the concourses. The major airport near me has several exclusive shops and one-of-a-kind restaurants out on the different concourses. You can't shop or eat there unless you have an air ticket. I think this sucks and it's not fair to the local residents.

        But you don't need an actual ticket, a boarding pass will get anyone to those shops and eateries. The TSA people don't usually bother scanning the boarding p
      • There is the minor difficulty of duplicating government identification showing that you are the person named in the tickets/records--unlike the dvd booth, it is *highly* probable that the person that paid for the ticket is there at the same time trying to board--with id.

        hawk
    • by peter303 ( 12292 )
      or like two people in the same airline seat. I flew 18 segments in 2007 and only two of them had empty seats.
    • Yeah, I'm sure the NTSB will have a great laugh when they find out that two people have boarded a plane with the intention of sitting in the same seat. I hear they always find it hilarious when an unauthorized "passenger" slips aboard a plane. They even have a special word for those people: terrorists. Just imagine if you get airborne: the NTSB will radio the plane, the pilot will make a u-turn, the crew will get flustered and stare at you, and the other passengers will "subdue" the shit out of your face, o
  • with something like GNU Barcode software and a template of printed out tickets, one might be able to take some nice vacations.

    you terrorist scum!
    • exactly, using GNU software!!!! Send this enemy of democracy back to Commiestan or wherever it is these filthy communists do their evil sharing.
  • Maybe I'm missing something salient, but all this says is if you change the membership number provided to the system, the system will use that instead of any other. The only difference is that instead of the number being provided via a keyboard, it's provided via a barcode.

    Nothing to see here, move along.
    • by schon ( 31600 ) on Monday December 31, 2007 @06:50PM (#21870916)

      Maybe I'm missing something salient, but all this says is if you change the membership number provided to the system, the system will use that instead of any other.
      Yes, you are missing something. And it's significant becaose of this:

      instead of the number being provided via a keyboard, it's provided via a barcode.
      Yes, and the people operating the machines that read these codes trust them.

      Think about this: you go somewhere that uses ID/membership cards with barcodes on it. Salesdrone asks for your card. If you just give them the number verbally and are security-minded, they'll probably ask for ID. However if you provide the card, they won't, because they the card *is* the ID.

      Non-technical people don't understand how barcodes work, so they assume that nobody else does either. So if nobody else understands it, then it can't be forged.
      • by Unoti ( 731964 )
        It's still lame. They shouldn't trust the input of the barcode, any more than a web developer trusts their input. Perhaps the membership numbers should be more sparse and difficult to guess.
        • by leenks ( 906881 )
          Or lusers trust phishing emails. They do because they don't know any better, and they likely don't care either.
        • by schon ( 31600 )

          They shouldn't trust the input of the barcode, any more than a web developer trusts their input.
          Perhaps if you were comparing the people who *designed* the barcode system to web developers you'd have a point, but expecting the same from a minimum-wage clerk who's never had any real security training and doesn't even know how the system works is a bit much.
          • That's the point - just as a web developer should write his web app to treat all input as potentially dangerous, the reader designer should write the reader's software treat the stuff it reads as potentially dangerous and falsified.
    • by jimmyswimmy ( 749153 ) on Monday December 31, 2007 @07:09PM (#21871046)
      I used to work at a semiconductor fab - basically a big chemical factory. Access control, security and timecards were all kept by a barcode system, printed on the back of your badge. I had a lot of fun making bar codes to see which would get me into places I shouldn't have been, like the spaces between the cleanroom walls, or the tunnel under the building, or the chemical storage area (that was a place I didn't ever like being in). Probably seems worse now than it did then.

      Back in elementary school we had a stored-value system for buying lunch, with security based on bar codes on little plastic cards. This was nearly 20 years ago and there was free software available then (on my Commodore 64? Atari? Can't remember) to generate bar codes. I made a couple, based on the ID numbers of friends, and gave them to the lunch lady, telling her that those cards were a bad idea. They never changed anything, though. These days I'd have been kicked out of school for that, though, if not arrested.
      • Sophomore year I accidentally cracked my student ID. It had a barcode on it with my student ID that we used to get access to meals. After getting fed up with having to hold the cracked one just right I ended up just printing off my own using a barcode font.

        I did use my own ID, but if I wanted to I'm sure I could have gotten free meals. The lunch lady didn't care. When a card got too bent up to be used I printed off 5 more (and then folded the paper to keep a stiff stock).

  • BART tickets in SF are magnetic, not barcodes, but I've been expecting fakes Any Day Now.
    • Re: (Score:1, Insightful)

      by Anonymous Coward
      Pre-y2k the BART ticketing system was extremely hackable and a lot of duped tickets were being made with magstripe writers. BART used y2k as an excuse to upgrade their systems, and the tickets are uniquely identified now so forging them is pretty difficult.
  • Great. (Score:3, Funny)

    by Rgb465 ( 325668 ) <gbk@in[ ]htbb.com ['sig' in gap]> on Monday December 31, 2007 @06:43PM (#21870882) Homepage

    The article also points out that boarding passes work on this basis -- with something like GNU Barcode software and a template of printed out tickets, one might be able to take some nice vacations."

    Great, now GNU Barcode will be classified as a terrorist weapon...
  • by russotto ( 537200 ) on Monday December 31, 2007 @06:54PM (#21870940) Journal
    Darn it, now Acme* is going to read this and put a stop to my fake-discount-card ways. (they'll accept any code with the right length and first three digits... amusingly including other supermarket's cards).

    *That's the grocery store, not Roadrunner's coyote-torturing company.

    • Re: (Score:3, Insightful)

      by bmsleight ( 710084 )

      amusingly including other supermarket's cards
      It good marketing to take other supermarkets discounts. Kind of like making sure Oo.o can read other file formats, it keeps you coming back.
      • by maxume ( 22995 )
        You misunderstood. The store isn't taking other stores discounts, it is treating a customer card from a different store as valid and applying its own discount to the purchase. The customer cards are used to correlate purchases and gather more information about peoples buying habits, in an attempt to make more money by marketing to them.

        The bigger discount stores don't bother, but I'm sure they correlate purchases that use the same credit card number, and I'm pretty sure that some of the custom coupons they
    • All stores that I've seen will allow you to get a "Club Card" or equivalent without giving any personal information. Also, the if you can find where they keep the unused club cards, from what I've seen they can all be used without being initialized. Oftentimes you can find some at a check lane, attached to applications, or at the self-checkout counter.

      Personally, I just use the phone number to my parents' house because they've signed up for all the club cards already.

      • All stores that I've seen will allow you to get a "Club Card" or equivalent without giving any personal information.

        But they probably link it up first time you slip up and use a debit/credit card to pay. Using different "cards" prevents that.

        So does using the phone number the last guy used. Or in a pinch, just make one up in a local exchange; the chance of it working likely isn't too bad. Hmm, I just had a thought... what if you give the store's own main number? They probably have a card keyed to that.

        • I think so. I used made-up name, address, etc., for a Safeway savings card. Of course, I used it with my debit card. Now, when I use it and pay cash the clerk always says "Thank you, Mr. Myname."
    • That's because Acme, Kroger, and a number of other stores use Catalina Marketing Corporation's services. Same cards work in different stores.
  • Nothing special (Score:4, Insightful)

    by markdavis ( 642305 ) on Monday December 31, 2007 @06:58PM (#21870970)
    There is nothing special or inherently secure about barcodes. They are just a machine readable number. Security has nothing to do with it- those are measures taken outside the barcodes. Anyone can print any type of barcode on just about anything.
    • Boy, you're a rather trusting person! The more complicated the barcode, the larger the number, the less likely it is that the software will have no security lapses. Imagine a barcode which you present to the reader that gives you a remote shell via its network? Or which modifies the barcode software so that it gives your code the privileges of the last person to come through?
  • by shlingus ( 1046986 ) on Monday December 31, 2007 @07:08PM (#21871036)
    Being able to print 2-dimensional, 3-dimensional, or even n-dimensional barcodes is useless no matter what software you have unless you already possess the inside info of knowing somebody's valid account number, data, etc. If somebody's gotten a hold of enough info to successfully print and use an illicit barcode, your security problem lies NOT with the barcode itself but with the system that allowed this information to get out in the first place.

    The same situation exists with magnetic stripes. If you have valid account data you can write it to a magnetic stripe on a card and go to town with it. It's getting the data that's the hard part.
    • Being able to print 2-dimensional, 3-dimensional, or even n-dimensional barcodes is useless no matter what software you have unless you already possess the inside info of knowing somebody's valid account number, data, etc. If somebody's gotten a hold of enough info to successfully print and use an illicit barcode, your security problem lies NOT with the barcode itself but with the system that allowed this information to get out in the first place.

      The same situation exists with magnetic stripes. If you have

  • Here we go again (Score:3, Insightful)

    by Flexagon ( 740643 ) on Monday December 31, 2007 @07:08PM (#21871040)
    Sounds like the brilliant utility companies of the '60s that trusted the billing and payment amounts that they sent to their customers on punched cards, and expected to trust when the cards were returned with "payment".
  • These types of small-scale scams have been happening for years - there's no reason to get into a panic about it now (unless it happens to be a slow-news day ..... New years, hmmm)

    Barcodes are pretty much obsolete so far as people's ID goes so the only organisations who might possibly take a hit are those that haven't updated their systems to "modern" mag-strip technlogy.

    If you wanted to try and scare people over the holidays - and there hasn't been a good scare for a while, so I suppose someone wants to

  • by steveha ( 103154 ) on Monday December 31, 2007 @07:22PM (#21871120) Homepage
    I remember reading about some guy who was stealing using bar codes. He would go to a store, and put a fake price sticker complete with a fake barcode on some expensive item; then he would take the item to the cash register, where the sales person would scan the bar code, the item would ring up as something less expensive, and he would pay the amount on the cash register. Sell the item at a large profit, then repeat.

    He made up the fake stickers at home. I believe he would buy one of the less-expensive item, and at home he would duplicate its sticker. He didn't even need to generate the bar code, he was just copying the one that was on there.

    Eventually he did the same trick too many times and they caught up with him.

    If anyone remembers details of this story and can post a link to it, please do.

    steveha
    • by bjorniac ( 836863 ) on Monday December 31, 2007 @07:41PM (#21871210)
      Been done a few times, but the one that comes to mind is this:http://www.denverpost.com/news/ci_3270764

      There was also someone who stole a bunch (something like $300k) of legos like this (yeah, geeks crime) and I remember a case involving Mall-wart and iPods...
      • This guy's problem was that he tried purchasing a $150 iPod with a $4.99 headphone barcode and naturally got caught. The better thing to have done(*) is to buy a top-end model of a product with a bottom-end model's sticker price. If you can achieve a > 2x price difference, then you can sell the original item at a hefty discount and make a profit. Was that the $149 iPod Nano or the $399 iPod touch? And if you're caught, you can easily feign ignorance as it's more likely that it was an employee labelin
    • When self-checkout machines first appeared in groceries I thought of this one.

      1) Go to your nearest grocery store that has self checkout machines as well as a weigh station in the produce dept.
      2) Pick up an expensive bottle of wine.
      3) Go to the produce section and put the wine on the scale and enter the code for a cheap item such as potatoes.
      4) Place the printed barcode sticker over the barcode on the wine bottle.
      5) Pay for your items using the self checkout. The machine verifies all purchases by ch
      • Re: (Score:2, Informative)

        by AnarkiNet ( 976040 )
        That doesn't work.
        The cashier's screen shows the SKU/UPC, abbreviated description, and price of each item on all self-checkout lanes attached to that cashier's station (usually 4). Unless the cashier is very green, or distracted by another customer, you will certainly get caught.
        However, scuffing up the barcode on an expensive bottle of wine that looks very similar to a cheap bottle, and buying both by trying to scan the damaged barcode on the expensive bottle, which won't work with the machine, then ty
    • I was buying my kid an Xbox wireless controller from Target, the lady was having trouble scanning the UPC so she went looking for other barcodes, scanned the serial number which got a hit in their system as something for $6.99 (she figured out that wasn't right and eventually got the UPC to work).

      I was pretty surprised that the S/N (or at least the left or right part of it) matched a UPC.
    • My old employer had a timecard & access control system that used badges with a barcode. I scanned the back of my card and after some tweaking of the scan settings (the basic scan wasn't sharp enough) I was able to print out a backup badge to keep in my wallet.

      Worked out pretty well, since I was prone to forgetting my badge.
  • by Anonymous Coward on Monday December 31, 2007 @07:23PM (#21871124)
    L33t hackers discovered that with a certain amount of awareness and bravado it is possible to obtain quite tasty sandwiches for free, by hanging around the pickup counter at sub shops and pretending to hold the ticket number that was just called out.
  • I have not seen the barcode, but this likely could be thwarted by using a simple checksum algorithm to add two digits to the end of the barcode number or somewhere within. This would prevent rudimentary attacks on the barcode by simply changing a few digits. The system could then check the number to see if the number 'checks out' prior to allowing access. This is valid of course, if an attacker does not figure out the checksum number. From reading the article, it sounds as if there is another system flaw.
    • A better way to defeat guessing would be to encrypt the SKU, ID number, etc and decrypted in the terminal... but at the end of the day any security you put on the barcode can be defeated with a photocopier. As others have pointed out the real problem lies with non-geeks not understanding the concept of trusted and untrusted data.
      • by DoomfrogBW ( 1010579 ) on Monday December 31, 2007 @09:43PM (#21871750)
        That is incorrect. While the barcode can be photocopied, a backend database with terminal-level authentication to verify the barcode would stop most people. Before passing to the server, the terminal takes the barcode and has the algorithm below for generating the checksum. The two are compared and if they match, then it is passed onto the server which provides the ultimate authentication. If the checksum's do not match, then it is invalid. This prevents someone from simply changing a few digits and thinking it will work, which is what the article is talking about. The following method is a popular means by which to combat photocopying. For instance: A barcode number in Code 128C can be given as 000000070314100601 then apply checksum security and add these last two digits to the end of the current number:

        // Generate CRC16 checksum using pos 1,3,5,7,9,11,13,15,17 of barcode

        unsigned short cs;
        cs = crc16((unsigned char*)barcode);
        barcode[18] = (cs / 10) + '0';
        barcode[19] = (cs % 10) + '0';
        barcode[20] = '\0';
        ...

        unsigned short __fastcall TFormMenu::crc16(char* p) {
        char checksum = 0;
        for (int i = 1; i <= 17; i += 2) {
        checksum = checksum + p[i] - '0';
        }

        return checksum;
        }
        • From TFA:

          The Phenoelites say that, by contrast, they have so far been unsuccessful in their attempts to crack the package collection slips used at the German Post Office's parcel stations, and the online tickets used by German railways. The two-dimensional codes of the latter have clearly been secured additionally with encryption methods, said FX, and this was something he strongly urged as a general practice for the proponents of automation.

          if you need data security you should be using the industry stan

          • Duh. I never said it was perfect and of course it can be trivial to reverse engineer. However, even if you do reverse engineer it, then you need a server backend to then provide the ultimate authentication. I think you are missing the point. Did you know what those numbers meant? Probably not. They are encrypted and obfuscated. A combination of those two factors and checksum makes the barcode more secure. Barcodes are inherently insecure unless you use encryption, obfuscation, and a checksum.
  • I had to look this up: a DVD hire shop is a movie rental store. Apparently the old-worlders use "hire" to mean "rent".
  • by BitterOak ( 537666 ) on Monday December 31, 2007 @08:36PM (#21871474)
    Anyone who has done any work with barcodes knows they are encoding schemes, not encrypting schemes. A barcode is simply a way of representing data (may be alphanumeric or binary), in a way that is easily read by scanning equipment. The commonly used algorithms are well publicized and it is easy to obtain software to read or write them. If security is important, encryption must be applied before the data is encoded in a barcode. I've scanned many barcodes on many things, and if money is involved, such as tickets or postage, I've generally found that they decode to seemingly random binary data, which means that most likely, encryption was applied first.
    • Encryption? Why encrypt when you can just use a unique, unguessable ID and store everything of actual interest on a secured server?
      • Encryption? Why encrypt when you can just use a unique, unguessable ID and store everything of actual interest on a secured server?

        Encryption gives you the ability to verify that not only was the data read correctly, but that it is invalid rather than just being unscannable. So you can still have an unguessable ID (eg: a GUID) that's stored in a database and correlates with the info of actual interest, but also encrypt that. Where this could come in handy is in areas where there's a higher incident of employee fraud or the need for greater security/trackability. Assuming you've dealt with the problem of someone simply walking out o

  • Blockbuster Online's envelopes that you take back to the store had all kinds of account information on them, including what type of account. However, it occurs to me that all it needs to have is an account key. They should be able to scan that and your store membership card (two-key system to avoid spoofing) to return the DVD and give you credit to rent your free movie. I noticed a recent minor change in their store policy, so they may have actually fixed this?
  • by matelmaster ( 1040950 ) on Monday December 31, 2007 @08:50PM (#21871532)
    The talk this Heise article is about (which was held at 24c3 on friday [events.ccc.de]) is actually available as a full-length download in various formats on mirrors [events.ccc.de] (look for "2273-en-toying with barcodes") and on bittorent [thepiratebay.org] along with most of the other talks given at this (totally awesome) event. And it's in english, too.
  • by TransEurope ( 889206 ) <[ed.znelbok-inu] [ta] [caine]> on Monday December 31, 2007 @09:17PM (#21871664)
    http://ftp.uni-kl.de/24C3/matroska/24c3-2273-en-toying_with_barcodes.mkv [uni-kl.de]

    See this website for mirrors, other video formats and the rest of the videos of the 24C3-conference (some of them are really interesting, videos with a 'de' instead of 'en' in the filename are in german). http://events.ccc.de/congress/2007/Conference_Recordings [events.ccc.de]

    Happy new year, gentleman/women :-D
  • Duplicate Tickets (Score:2, Insightful)

    by Tablizer ( 95088 )
    The article also points out that boarding passes work on this basis -- with something like GNU Barcode software and a template of printed out tickets, one might be able to take some nice vacations."

    What if the rightful owner shows up with the same ticket number? Unless the tracking software is lame, it should note that a given number had already check in. At that point, an investigation would ensue. The perpetrator is probably caught on camera for non-trivial travel and the time stamp of check-in and the
  • by ZonkerWilliam ( 953437 ) * on Monday December 31, 2007 @10:50PM (#21872048) Journal
    I don't see much to be concerned about. "Hacking" them isn't really new, switching UPC stickers has occurred for decades, and as mentioned by another reader, it's considerably small instances. The best place to put security worries is in the bar-codes offshoot, RFID tags.
  • Or at least not more than at the moment. I just had an international Flight with e-checkin. Would have been trivial to print several boarding passes (you print them yourself) with different names. I don't remember whether it had a barcode, but at boarding they just kept the second printout. Admittedly this was from Switzerland to Austria, but still.

    I don't think barcodes are a security risk at all. Reliance on stuff that any modern printer can do is.
  • by 6Yankee ( 597075 ) on Monday December 31, 2007 @11:10PM (#21872132)
    ...is the Trojan zebra camouflaged within.
  • I find it a bit surprising that no one's yet mentioned the free 3of9 barcode font [barcodesinc.com] .

    Back when I had a working scanner / OCR setup, I spent a lot of time trying to reverse-engineer the barcodes on coupons. You might be surprised how lenient cashiers are with those things these days... even after a former co-worker of mine printed up (and handed out) about 1,200 self-made "Free 20oz Coke Product" coupons.

    With internet-printable coupons more popular than ever, I wonder how long it'll be before we start se
    • There isn't really that much in the way of reverse engineering involved. You just need to know what coupons the till accepts at the moment, and print out the one you like the best.

      If you look at for example Thresher Wine Shop in the UK from last year (holiday season 2006-7), they had a problem with people distributing discount coupons all over the internet.
    • The grocery store I go to totally stopped accepting internet coupons for along time, they now accept certain ones that they have preapproved. If you have a new one you can give it to them before you start shopping and they will approved it while you shop.
      IIRC when they first stopped accepting them they said there were sites that provided printable coupon complete with scannable barcodes for common items that were in the range of buy one get one free.
  • I work at Kohl's Department Store and their in-store credit line ('Kohl's Charge') uses a barcode on the back of the 'credit card' to charge your account- there is no magnetic stripe. The 'numbers' the barcode represent are clearly printed under it.

    All it would take is some clever kohl's employees, get a big list of kohl's charge numbers, make cards with names corresponding to whatever ID you have.. bingo..

    Oh, the most hilarious thing is with Kohl's... if you lost your card, you can go into the store and a

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