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Modem jacking

What is modem jacking?

Modem-jacking (also known as ‘dumping’) changes the dial-up number used to access the internet. These scams direct the victim’s computer to dial into the internet using an overseas or premium rate phone number, instead of using the normal ISP. The new provider may charge hundreds of dollars per hour.

Modem-jacking occurs when a program is downloaded onto your computer. Sometimes this program is downloaded without you agreeing (for example, as a virus when you click on a link in a spam email). In other cases, the program will be disguised as a program that allows access to certain websites such as adult or free music sites.

Sometimes, however, people agree to download these programs. For example, some adult websites offer access to their site with the cost discreetly added to your telephone bill. To enable this, you have to agree to a program being installed on your computer that will change the telephone number you use to connect to the internet.

If the full cost of connection is clearly given in the terms and conditions, these systems are not illegal. The website owner hopes that you agree to this attractive solution without checking the contract conditions. On the other hand, if you are misled about the charge rates, or if the program connects you to the internet without you agreeing, than this is modem-jacking and is a scam.

As more people move from dial-up connections to broadband, the opportunities for modem-jacking are decreasing. However, if you have a dial-up modem connected to your computer (or an internal dial-up modem), you may be vulnerable to modem jacking. If you have a dial-up modem that you are no longer using, you should disconnect it from your computer if you haven’t done so already.

Warning signs

You visit a web site that:

  • encourages you to use an alternative payment method involving the installation of a piece of software
  • enables your modem to re-dial on the internet
  • offers to bill you through your telephone or telecommunications company.

You may also notice that:

  • your telephone bill is much higher than it normally is
  • your computer is running slower than normally
  • there are new or unusual icons on your computer screen
  • you hear your (dial-up) modem disconnecting and then dialling when you have not asked it to.

Protect yourself from modem jacking

  • Use your common sense: the offer may be a scam.
  • Install software that protects your computer from viruses and unwanted programs and make sure it is kept up-to-date.
  • Beware of free websites and downloads (such as music, adult sites, games, movies). They may install harmful programs without you knowing.
  • Read all the terms and conditions of any offer very carefully: claims of free or very cheap offers often have hidden costs.
  • Be careful of phone numbers beginning with 190. These are charged at a premium rate and can be very expensive.

As well as following these specific tips, find out how to protect yourself from all sorts of other scams.

Do your homework

Always read contracts, small print and disclaimers in full and make sure you know what you are agreeing to. This is especially important before agreeing to a contract on the internet because with one click you can commit yourself.

If you don't want to read all the disclosures, then don't agree to the offer. If you do agree be prepared to suffer the consequences! Read the pop-up windows which should appear when you download files from the internet. The pop-up window may provide information on redirection and charge rates.

For more information on this type of scam, visit the ACCC website’s modem jacking page.


If you are not totally sure about a download or about accessing a particular website, ask yourself whether it is worth the risk to proceed.

If you use a dial-up modem, or still have a dial-up modem installed on your computer (even an internal dial-up modem), consider barring all 190 (premium rate services) calls from the phone line you use. You can do this by contacting your telecommunications provider.

Also make sure you tell everyone who uses your internet account how to protect themselves from modem-jacking.

Remember: only agree to contracts you understand.

Report them

If you think you have been the target of a modem-jacking scam, you should report it to your internet service provider, your phone company (if it is not also your ISP), and through the report a scam page of SCAMwatch.

You should also disconnect your dial-up modem and get the modem-jacking program removed from your computer (you may need to take your computer to a professional as sometimes these programs can be difficult to delete).


What to do if you've been scammed; Scams & the law; Report a scam.

Similar scams:

Online auctions can be rigged by scammers or used to target you for a scam outside of the auction site. You could end up with a dud product or nothing at all for your money.

Scams that send you a fake renewal notice for your actual domain name, or a misleading invoice for a domain name that is very similar to your own.

Spam emails, SMS or MMS usually offer free goods or ‘prizes’, very cheap products or promises of wealth. Responding to spam messages can result problems for you computer and your bank account.

Offers of ‘free’ website access, downloads, holidays, shares or product trials – but you have to supply your credit card or other personal details.

Spyware is a type of software that spies on what you do on your computer. Key-loggers record what keys you press on your keyboard. Scammers can use them to steal your online banking passwords or other personal information.

Missed calls that can lead to premium rate charges. Mysterious text messages that can cost a lot of money if your reply to them.

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