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Telus Puts A Stop To 'Modem Hijacking' 293

Posted by simoniker from the relatives-in-sao-tome-most-upset dept.
TheIonix writes "Telus, a major telco in Canada, decided to block long distance direct-dialed calls to four countries to help reduce dial-up 'modem hijacking'. The article explains: 'When the [dial-up] user downloads [certain malware programs], the downloaded file accesses software on their computer and causes the modem to dial phone numbers in foreign countries, resulting in long distance charges.' 4 countries were targeted: Guinea-Bissau, Guyana, Nauru and Sao Tome. It is still possible to call to those countries with the operator assistance and the fees are waived. Now let's see if this nice idea will be followed by others."
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Telus Puts A Stop To 'Modem Hijacking' More

Telus Puts A Stop To 'Modem Hijacking'

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  • When phone monopolies go corrupt... (Score:5, Informative)

    by LostCluster ( 625375 ) * on Tuesday June 29, 2004 @12:32PM (#9562036)
    Commonly, the way that these international calling scams work is that the monopoly carrier of the foriegn country charges obscenely high rates by most standards, and then the malware writer leases lines close to the point of entry so that the carrier doesn't have to do much work once the call enters their system. The malware writer is then given a piece of the international call toll for attracting the business.

    In short, the phone companies in these developing nations are usually in on the scheme and profit just as much as the malware operators do from the increased call volume. They have no interest in stopping calls that way.

    I wouldn't be opposed to giving such companies an international telecom death penality of simply not routing calls their way. If the only phone operator in a country can't properly keep scam artists out of their network, and furthermore aids such scam artists, that country really doesn't have much of a phone system to begin with... an electronic embargo might get the government there to get a clue.

    • Re:When phone monopolies go corrupt... (Score:5, Interesting)

      by Bellyflop ( 681305 ) on Tuesday June 29, 2004 @12:41PM (#9562171)
      A friend of mine works for a porn billing company. A lot of their customers use dialers. They don't hit the US because there are too many laws concerning it, but you'd be suprised at how many countries (like Australia) where their business is really booming. It sucks. It shouldn't be happening. But he makes a killing on it.

      To his credit, he doesn't write the dialers themselves. He just writes generalized billing systems for porn sites which are the ones putting dialers on people systems. Usually they wait until the wee-hours of the morning or during the day to make their calls so they can stay connected for a good 2-3 hours and really rack up the charges.

      I wouldn't go after the phone companies so much as I would go after the dialer producers. I think generally it's not that the phone company is in cahoots with the dialer company, it's just that they don't bother to regulate it or their government hasn't passed laws officially banning the practice. Governments usually get off their rear and do that but it takes time. Besides, there are probably legitamate reasons for calling those countries such as talking to one's family.

      • Re:When phone monopolies go corrupt... (Score:4, Interesting)

        by LostCluster ( 625375 ) * on Tuesday June 29, 2004 @12:46PM (#9562240)
        Still, a phone company somewhere has to be offering the billing service that these dialers are using to cash in. Either it's an interational call to a phone operator that's in on the scheme, or it's the local version of 1-900 area code or 976 exchange pay services.

      • The telco *has* to be in cahoots... (Score:5, Interesting)

        by blorg ( 726186 ) on Tuesday June 29, 2004 @12:54PM (#9562338)
        ...with the dialer company (the telco in the foreign country, that is) - otherwise the dialer company would not make any money! The only way that the scam can work is that the foreign telco passes on some of the call revenue to the dialer company. Having said that, in some countries the home telco should also be held responsible - for example, here in Ireland the monopoly telco has specifically put all of the 'dialer countries' into a special band, for which they charge 360c/min, [comwreck.com] *three times* what they charge for the next band down (122c for 'rest of Pacific Rim'). As such, they make substantially more than the dialer companies themselves out of these scams (which doesn't motivate them to fix the problem.)

        I think generally it's not that the phone company is in cahoots with the dialer company, it's just that they don't bother to regulate it or their government hasn't passed laws officially banning the practice.
      • If I ever found a third world country, I'll have to keep this in mind. Great way to pad the ol' treasury, eh? ;-)

        Seriously though, what would happen if you simply refused to pay the charges? i.e. Work with your phone company so that you pay them their side of the line, then simply refuse to cough up the cash to the foreign carrier. Attempts at prosecution would have to be through your home country's legal system, which may have laws regarding fraudulent debts.
        • Seriously though, what would happen if you simply refused to pay the charges? i.e. Work with your phone company so that you pay them their side of the line, then simply refuse to cough up the cash to the foreign carrier. Attempts at prosecution would have to be through your home country's legal system, which may have laws regarding fraudulent debts.

          It's black mail. Do you really want to go to court with "Nude 17 years olds of Nigeria inc." and risk getting a rep as a porn fiend? Not that many do so this f
      • To his credit, he doesn't write the dialers themselves. He just writes generalized billing systems

        Yeah. For a second there, I thought your friend sounded like an unscrupulous piece of shit, but knowing that he doesn't actually write the diallers themselves has given me new respect for him.

        What's your point exactly? This sounds like a lame excuse to absolve someone of responsibility for supporting behavior of dubious legality and even more dubious morality.

        Guess what? A good case could be made that so

      • Go after the dialer producers?? (Score:5, Insightful)

        by PetoskeyGuy ( 648788 ) on Tuesday June 29, 2004 @02:11PM (#9563247)
        That's very stupid. They should go after your friend and people who make money from others. You can bet some poor sucker got paid $50 or less to write the dialer if they even got paid. Once it's made, you have it, just change the number it dials.

        It's the telco's and the porn companies that need to be held accountable since they are the ones distributing and profiting from this computer hijacking. They could possibly face jail time for that if they are in the US. Not sure, but it seems there are stricter laws all the time.

        Writing a dialer is pathetically easy. Even from a simple DOS prompt, one liner
        echo "atdt 1-123-456-7890" > com1:

        This is once step BELOW spammers in my opinion, and your using the same pathetic excuses they do. People shouldn't make it so easy to do. Spam at least is only for idiots. Your taking control of computers and waiting until people won't notice.

        It's not email software or dialer software that is the problem. It's the scum who take these useful tools and use them to try to rip people off.
      • The problem with going after the producers and distributors of the dialer software is that it ends up being whack-a-mole. Any scam artist worth their salt is perfectly capable of shutting down one scam under legal pressure and opening a new one. Going after the telcos is much easier, even if the dialer agents are more culpable.

    • Not even that..... (Score:5, Interesting)

      by spectrokid ( 660550 ) on Tuesday June 29, 2004 @12:46PM (#9562239) Homepage
      A consumer protest broke out about this in Denmark some time ago. The first IP adresses encountered when dialled in were in.....London. The operators charge the long distance call, but your phonecall actually never reaches the country of destination. The blocking described is now standard for all Danish telco's.
    • How many of those monopoly phone companies are government monopolies? "Posts and Telecoms" remains within the government in many places.
      • At most one of these Nauru remains a government monopoly. Two of them, Sao Tome and Guinea-Bissua are owned in part Portugal Telecom which seems to be a former Telecom monopoly, now privately owned. The other, Guyana is a majority owned by ATN, an American company.

        So it seems it isn't 'the corrupt third world governments' behind this 'problem'.
    • Do you have any actual evidence that it is the national carriers in these countries that are actively encouraging this? Yours is an interesting post, but then again, you assertion that "the malware writer leases lines close to the point of entry so that the carrier doesn't have to do much work once the call enters their system" suggests you don; have a clue how the PSTN works.
    • This isn't restricted to the phone companies of the country that the dialer is calling. Eircom, the irish ISP, actually charge additional rates of up to 6 euro a minutes when one of the known dialer numbers is called!

      Still, free email addresses. Can't beat that.

  • Lesser of 2 evils I suppose (Score:5, Insightful)

    by tekiegreg ( 674773 ) * <tekieg1-slashdot@yahoo.com> on Tuesday June 29, 2004 @12:33PM (#9562047) Homepage Journal
    Granted auto dialers to these countries will no longer function, but I suppose the loss of the one customer who regularly dials Guinea-Bissau, Guyana, Nauru and/or Sao Tome in Canada vs. the gazillions of mad people for bum phone bills weighs itself out. However let's see them try this with a bigger country having auto dial issues as well (Thailand, Vietnam and former Russian republics come to mind). A step in the right direction, but not hardly a full solution.
    • I'd estimate that in the case of these smaller places, a majority of the phone calls they were getting from Telus were being disputed as illegitimate. Countries with larger populations would have more legit calls being made to it, and therefore it'd take many more problem calls to get to the same percentage ratio.

    • Re:Lesser of 2 evils I suppose (Score:5, Insightful)

      by afidel ( 530433 ) on Tuesday June 29, 2004 @12:40PM (#9562148)
      My guess is that less than 1/1,000th of one percent of their long distance traffic targets the countries in question yet these malware programs result in more than one percent of their billing complaints. My personal solution would be to do exactly what they have implemented with the additional remedy of being able to remove the call block for those customers who so request. They can already do this with 900 blocking so the ability should either exist in their software or be easily added.

      • My cell phone provider defaults to having international dialing completely disabled. You need to call and go through a verification process to enable it.

        There's a catch, though: It's either all on or all off. You can't say "I've got my wife overseas in the Philippines for a few months, and a friend in the UK. I'd like to be able to call those two countries, but please leave everyone else blocked."

        No good excuse for that, either. It's hard to believe they can't have that level of granularity. What I'd re

    • Given that customers can still place calls to these countries by using operator assistence I don't think this is too much of a problem.
      • So now I have to configure UUCP to call the operator at 23:30 at night? I don't think that will work.

        And yes, some people do still run services using intercontinental UUCP links.

        This better be configurable on a per subscriber basis.

    • Why would it be a loss of a customer? You direct-dial like you would have in the past, but instead of being connected directly an operator confirms that you intended to make the call. You are charged direct-dial rates, not operator assisted rates.

      What could be simpler?

    • Re:Lesser of 2 evils I suppose (Score:4, Interesting)

      by king-manic ( 409855 ) on Tuesday June 29, 2004 @01:21PM (#9562647)
      Better solution:

      voice conversations are very very tolerant of small disruptions while data is not. So just introduce random noise once at the beggining (to interrupt the initial handshake) and once every minute of so. a small change in pitch and modulation 1/2 second out of a minute won't affect voice calls very much but data lines won't take it too well.

      Not that many people place Long distance data calls on land lines. Some geek BBS'ers but their pretty rare in this age of telenet. So there'd be very very little disruption of normal service.

    • Re:Lesser of 2 evils I suppose (Score:4, Interesting)

      by grolschie ( 610666 ) on Tuesday June 29, 2004 @06:40PM (#9566171)
      In New Zealand this problem was recently on primetime TV. In response, one of our tollcall providers has implemented a change where a confirmation message is played upon dialing a certain few countries, and the caller has to press a key in response. This is simple enough to implement and would be pretty affective. Porn-Dialers would have to be a little more clever to get around this.

  • This is good (Score:4, Insightful)

    by bunburyist ( 664958 ) on Tuesday June 29, 2004 @12:34PM (#9562053)
    Telus needed to do something, I know from experience that this is a serious problem. 16 dollars for some call to africa i never placed, I had no idea about this stuff, fortunately Linux is immune to these things. Here's an idea: Don't hook up the phone line to the computer unless you plan on going online. That way if one of those stupid dialers fire up, its evil plan will get foiled.

  • Another idea (Score:5, Interesting)

    by drinkypoo ( 153816 ) <drink@hyperlogos.org> on Tuesday June 29, 2004 @12:34PM (#9562058) Homepage Journal
    Why not just have a system that speaks some digits and waits for you to punch them back in for verification? I doubt this software is going to figure out the drivers for your voice modem and do speech recognition.

    • Re:Another idea (Score:2, Insightful)

      by marnargulus ( 776948 )
      Because that would be a huge hassel to implement compared to the 1 operator it will take to handle these calls to countries most people don't know exist. When was the last time you called Sao Tome(of your own will)?

    • Better yet (Score:5, Insightful)

      by ad0gg ( 594412 ) on Tuesday June 29, 2004 @12:44PM (#9562214)
      Most of these international telecom LD companies use voip, and the gateway will negotiate to the right codec depending on whether its a data or voice call. Have the carrier detect whether its a voice call or data call and drop on the results.
      • People may have a legit reason to want a data connect with the given countries, and it usually is a violation of privacy law to do such detection without the customer wanting it. It's a great tech solution but a dumb policy.
        • People may have a legit reason to want a data connect with the given countries, and it usually is a violation of privacy law to do such detection without the customer wanting it.

          No it's not. If it were, 56Kbps modems wouldn't work, because they depend on the telephone exchange to detect that it's a modem connecting, and to set up a data call. All telephone companies use systems that do this. Rejecting data calls by policy is most certainly built into all the digital exchanges.

          Most European countries even
        • When was the last time you did a data call to Guyana? List soem legitamate reasons. BBS's? that about it. and odn't tell me Gayana is a BBS mecha that all geeks must dial once in their life times or face eternal damnation in the microsoft campus.

  • Phew (Score:5, Funny)

    by grub ( 11606 ) <slashdot@grub.net> on Tuesday June 29, 2004 @12:34PM (#9562068) Homepage Journal

    I'm glad Nigeria isn't being blocked, I have to contact Dr. Mbugo Mbongo to see how my wire transfer went.
  • If not a bit late, though seems like the wrong approach to the problem, but perhaps as much as the phone company can do about it.

    Of course, I personally haven't seen a modem in years... ;-)

  • Not really "putting a stop to it", are they? (Score:3, Insightful)

    by lightspawn ( 155347 ) on Tuesday June 29, 2004 @12:35PM (#9562082) Homepage
    It only affects their customers, and only with malware dialing to four specific countries.

    With that kind of sensationalist headline, you'd think they released a benevolent worm that safeguards against hijacking.

    Seriously, is following the money, reversing the charges and putting the people responsible behind bars all that difficult?

  • Operator Assisted Modems (Score:5, Funny)

    by Bastian227 ( 107667 ) on Tuesday June 29, 2004 @12:36PM (#9562086) Homepage
    It is still possible to call to those countries with the operator assistance.

    Operator: How may I direct your call?
    Customer: Squeeechhllcshhsh
    Operator: You want to be connected to Guinea-Bissau?
    Customer: Squeeeeelch
    Operator: One moment while I connect you.

    See, it won't help. :)

  • Pay us to not provide a service to you? (Score:3, Informative)

    by LostCluster ( 625375 ) * on Tuesday June 29, 2004 @12:37PM (#9562104)
    Telus's CallGate service costs $3.95 (Canadian, of course) and gives the option configure it to block 1-900 calls, toll calls, a list of 25 specific numbers or such.

    It's interesting that they're asking people to pay to be not able to dial given numbers. You'd think a hardware device on the user's side could provide the same functionality for less...

    • Re:Pay us to not provide a service to you? (Score:5, Interesting)

      by Tackhead ( 54550 ) on Tuesday June 29, 2004 @12:46PM (#9562232)
      > It's interesting that they're asking people to pay to be not able to dial given numbers. You'd think a hardware device on the user's side could provide the same functionality for less...

      Problem with (commercially) building something designed to plug into the phone jack is that there's a lot of paperwork involved.

      Such a device would be a very cool homebrew project, though. Just intercept the DTMF for "1" and a user-configurable series of digits (you could program the device either with a keypad on the device, or you could program the device with DTMF tones). Hold the dialed digits in a buffer. When the user finishes dialing the digits on the phone, the user presses the "dialout" button on the phoneblocker, and the buffered digits are dialed out. (Sorta like a cell phone - punch in digits, then click "OK" to dial)

      Because a trojan dialer isn't going to have you around to press "dialout", no call ever gets made. Added bonus, you have a gadget that can log the numbers (and for real style points, add a clock chip and store time and date :) all outbound calls made from your number.

      Of course, anyone smart enough to design it - or even just build it from a set of schematics and a bucket of spare parts - is unlikely to get pwn3d by a trojan pr0n dialer in the first place. But it'd be a fun weekend project or group exercise for a first year engineering course.

    • You'd think a hardware device on the user's side could provide the same functionality for less..
      its called unplugging the phone cord
      the software solution is called ad-aware/spybot S&D
    • You mean like this [radioshack.ca]? C$69.99! Having worked for RS in the past, I have used this device and you can program it to block specific numbers, long distance numbers, etc.

  • so the malware writers will just... (Score:3, Insightful)

    by Anonymous Coward on Tuesday June 29, 2004 @12:38PM (#9562113)
    make the programs dial different countries. simple.

    then the telcos will block those countries...
    until we need operator assistance to dial anything!
    (extreme)
    • well.. there are not that many telcoms in the world that are willing to keep such customers that generate revenue through those dialers, basically you have to be in bed with the telecom somehow(through bribery most probably in most cases).

    • It's really not that simple. The way these people make money, it by providing telephone service to certain numbers in a remote.

      A few years back, in Denmark, there was a big deal around calls to St. Helena. The provider for these islands is British Telecom, so these were routed through London, and ran at about 20 dkr/min (=$3-4). About 1 or 2 dkr was the cost of the call to britain, and thus shared by the danish and british (legit) telcos. The rest of the money were paid to the malware-people to whom BT app

  • in sweden.... (Score:2, Informative)

    by Anonymous Coward
    telia, the major telecom company here have created software (free to download from their site) for ms windows that blocks mode hijacking attempts.
    • Who would have known that format.com was swedish...
    • I have software that blocks modem hijacking attempts and just about any other malware.

      Mozilla Firefox.

      Any other non-IE-based browser (on Windows) or IE running on a non-Windows platform (like MacOS or Solaris) will work as well. It's the IE-Desktop link that most malware uses to attack.

  • How many people still use modems? (Score:3, Insightful)

    by Paul Slocum ( 598127 ) on Tuesday June 29, 2004 @12:41PM (#9562156) Homepage Journal
    Seems like this problem may soon be eliminated by obsolescence.
    • 40-50% of the Internet users in the United States still use dialup. That's TENS OF MILLIONS [/pinky] of users, many of which will NEVER get high-speed due to their location / technical savvy / budget. Someday, maybe modems will be obsolete, but by no means will it happen "soon"; I'd say 20-some-odd years from now, maybe.
  • For one, do you really think they were giving people refunds for these charges? Maybe Canada has some consumer protection laws or something, but from my dealings with scummy utility companies in the US, I know I'd pay every penny for a hijacked modem.

    Then on top of that, this seems such a small fix. What happens when the new virus out sets it up to call, say, Russia or China. Can't exactly block those countries. Yes yes I didn't RTFA so I'm not sure if these countries have significance more than I kn

    • For one, do you really think they were giving people refunds for these charges? Maybe Canada has some consumer protection laws or something, but from my dealings with scummy utility companies in the US, I know I'd pay every penny for a hijacked modem.

      In Canada you are responsible for phone calls made from your phone, and you must pay for them. As Telus point out in their article, they have contracts for overseas calls, and the calls must be paid for even if the other end are corrupt scum.

      Exactly what

  • Local (Score:2, Informative)

    by Gettinglucky ( 655935 )
    I live locally to telus and one of the local television stations reported on this and said that cable modems and ADSL modems where also affected. They failed to mention anything about needing a phone modem connected to a phone line for this to affect the cable and ADSL modems. One way to create more excitement!!
    • No, you can rack up long distance charges over the internet no matter how you connect. Check out this [bash.org] reference for more facts.

  • Internet credibility of a country (Score:5, Insightful)

    by gtrubetskoy ( 734033 ) on Tuesday June 29, 2004 @12:44PM (#9562211)
    I think we are seeing an interesting trend where some countries are earning a bad reputation on the Internet, which will ultimately affect their economies and ability to participate in international trade.

    E.g. who in their right mind accepts credit card orders from Romania, Russia or Indonesia when it is well known that the vast majority of those card numbers are stolen?

    But I think that what is right now simply a major annoyance to on-line vendors and users (spam, phishing, etc.), will eventually backfire at the countries that are unable (or more likely do not care to) to control Internet fraud of various kind sas they become more and more blacklisted and left out of the Internet economy. This will eventually force their governments to pay attention to the issue. I bet already it is pretty frustrating to be an Internet user in one of such countries and know that most vendors on the internet will not accept any payment from you simply because of your country of origin...

    • Try and order jewelry from amazon.com

      They accept orders from all 48 states :-)

      (or occasionally 50. Tough luck if you are in Pago Pago or Puerto Rico, let alone a foreign country).

  • Where can I get this autodialler script for linux? (Score:5, Funny)

    by dogsbestfriend ( 755362 ) on Tuesday June 29, 2004 @12:52PM (#9562307)
    amazing. I never thought anything would do that on my toshiba laptop running linux. It was hard enough setting up any kind of dialling on the linmodem, if those scripts would have set up my modem for me and dialed a number, I would have gladly paid for it :)

  • Talk about a phone call... (Score:3, Funny)

    by pctainto ( 325762 ) on Tuesday June 29, 2004 @12:54PM (#9562336) Homepage
    I am sad to say that I was caught by one of these auto-dialers about 7 years ago. I was looking for porn (in 8th grade, I think) and saw one of these "free porn" dialers. Anyway, I heard it dial and everything -- but I didn't think it was international. Anyway -- I was stupid and actually stopped looking at porn after maybe 5 minutes, and stayed on the line, browsing, for an hour. The call cost my parents $500. My mom got the bill and immediately called to complain and AT&T said it was a pornographic number, so they nailed me. Anyway, my mom complained to the company that I was just a supid kid, and they waived the fee. So, my mom, who was about to pay this $400 was so happy that she got it waived that she bought me a digital camcorder ($800) for Christmas (which was about a week away). Who said porn never pays?

  • Implement free highspeed internet for all of your country! Then people can't use the excuse it costs too much!
  • What about putting code -- in the modem, the OS...somewhere -- that requires the user to verify the call before putting it through? Password it, too, to prevent an automated dialer from doing an end run.

    Or, why not just password modem access?

  • Telus not the only one (Score:3, Interesting)

    by Malc ( 1751 ) on Tuesday June 29, 2004 @01:01PM (#9562431)
    According the to end of this story [bbc.co.uk], British Telecom are going to start doing the same thing too.

  • Old trick (Score:3, Funny)

    by Cyberhwk ( 778308 ) on Tuesday June 29, 2004 @01:03PM (#9562445)
    This is something that has been going on for a while now. I remember this happening when I was in middle school and when my dad got wind of this trick he kept panicking thinking that I would download some malware. I never had an issue with this and the only one who was likely to do something like this was my mother. She used to want to download that purple monkey thing and it took me a couple months to convince her not to do that anymore and finally I just got sick of having to fight all the stuff she downloaded and reformated her computer. Since then she has not downloaded random things.

  • Did the calls ever go to those countries at all? (Score:4, Informative)

    by Animats ( 122034 ) on Tuesday June 29, 2004 @01:15PM (#9562572) Homepage
    The FTC has already acted in a porn dialer case. [ftc.gov] In that case, the calls were addressed to a country code in Madagascar, but were actually routed to London. There was another case where high-rate calls were routed to Canada.

    Usually, these scams involve some marginal "billing service" provider. Integretel, eBillit, Payment One, and Verity International are some of the names that come up.

  • Better Solution (Score:3, Insightful)

    by Billy the Mountain ( 225541 ) on Tuesday June 29, 2004 @01:15PM (#9562574) Journal
    Offer a free international call blocker to all subscribers and allow them to block out all the countries they are reasonably sure they would never call. When you try to call a foreign country that's blocked, a recorded message gives instructions on the procedure for removing the block.

  • Protecting its own interests (Score:5, Insightful)

    by Anita Coney ( 648748 ) on Tuesday June 29, 2004 @01:18PM (#9562599) Homepage
    Telus is not doing this to protect its customers, it's doing it to protect is own bottom-line. I would imagine that the vast majority of people caught by the modem high jacking scam refuse to pay their bills. They call and complaint, Telus backs down, and it is stuck holding the bag.

    This strategy ensures that Telus is never stuck again, plus, it gives them good PR because it appears that it is looking out for its customers. Yeah right.

    • Re:Protecting its own interests (Score:5, Insightful)

      by Idarubicin ( 579475 ) on Tuesday June 29, 2004 @02:10PM (#9563223) Journal
      This strategy ensures that Telus is never stuck again, plus, it gives them good PR because it appears that it is looking out for its customers. Yeah right.

      In this instance, a company can do something that

      protects their bottom line and shareholders;

      protects their customers; and

      screws the malware writers;

      and you're bashing them?

      Hey, I'm thrilled that a company is making more money while doing something that's good--even if it is a telephone company. What's wrong with a little enlightened self-interest?

  • Telus and SaskTel are doing the same thing. Read at CTV [globetechnology.com]

  • I ran into an individual that paid out for this, several hundred dollars. The problem though, is that he is a dialup user. The other problem is that he only has a single phone-line.

    When not in use for the net, the phone-line is disconnected from the modem... since the fax machine or something like that uses it also.

    Telus charged him for such a call... but it seems to me that he couldn't have even made it:

    -Phoneline likely disconnected
    -When connected, phoneline was already dialed out (can't double-dia

  • Telco Security Insider View (Score:5, Interesting)

    by Anonymous Coward on Tuesday June 29, 2004 @02:29PM (#9563450)
    I apologize for posting anonymously, but I'm under non-disclosure on this. I work in the security department of a major long distance provider. Telus's blocks are a good try, but they won't stop the problem. They will put a small dent in it, though.

    First of all, it's more than those four countries, although that's about half of the most common ones we've been seeing lately. At the very least, they should have added Diego Garcia, Tuvalu, and Tokelau to the list. But almost every really small, really poor country telco goes in for this kind of thing sooner or later, and at one point so did one of the UK telcos and (oddly enough) so did one of the Canadian telcos.

    Do not assume that there has to be a modem on the other side. Your modem doesn't have to sync for you to get charged, it just has to stay dialed into that number long enough for the "first minute" charge to take effect.

    The billers keep insisting that everybody who gets billed for these calls has agreed in advance to do so. At least some of them are lying about this. We have seen cases where we're absolutely sure that unlabeled trojans were to blame, including one that sets the user's computer to do so at least once a day for up to a couple of hours when they're not using it.

    There are only two completely reliable defenses against this. The only completely reliable was is to never, ever, ever plug an analog phone line into your computer. (I had one customer insist that it couldn't have happened to them, they used broadband. But they had a fax modem card, and the dialer detected and used that.) That's not practical for most people, so instead call your local phone company and ask for a total block on directly dialed international calls. Most companies offer this as a free service. Also make absolutely sure, if you never intend to charge premium services to your phone bill, that you tell this to your local and long distance phone companies; having that note in the records on your account will help their security people know to block the calls more quickly when they get by and may, the first time, help you get the charges removed from your bill.

    You can ask your long distance provider to block international directly dialed calls, too, but that'll only help if you get that block from every long distance provider in your country, and in the US that could take you weeks of research because there are so many. But if you're in the US and you don't block every long distance provider, all the dialer authors have to do is preface the modem string with 10-10 and the three-digit carrier code to temporarily switch your long distance provider. That's why it's going to be a lot more reliable if you do it through your local phone company, if they offer the blocking feature you need.

    After you've blocked the feature, if you absolutely have to make a directly dialed international call, call your local company and your long distance company, remove the block, wait for it, make the call, and then call them back and restore the block.

    US long distance companies aren't blocking whole countries for this because US law won't let them. Telcos are required to deliver every call that you want them to. This means that while we can temporarily stop your service until we can ask you "did you really want to make that call?," we can't pre-emptively stop you from calling poisonous numbers like this because we can't prove that nobody wants to call them. On the contrary, probably about 1 out of ever 20 customers that I speak to about this really did use the dialer on purpose and they intend to pay for the call. (About 3/4 of the callers, though, had it happen because somebody who didn't have their permission to charge long distance calls was sitting at the computer surfing porn or using paid gambling sites without the owner's knowledge. Frequently, it's their kids.)

    My employer doesn't want me to tell you this because it is their opinion that every time we reveal anything about what we know about this scam (or any other),

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