A Primer on Modem Hijacking

Definition

• Modem Hijacking is a form of "high-tech cramming" that can potentially cost a consumer thousands of pesos and could happen if you use a dial-up modem to access the Internet.

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How

• The most common way this occurs is when you visit a website and download software called a "dialer".
  
  Sometimes though, this software can be downloaded into your computer even without your knowledge, through ActiveX scripts. (ActiveX is a technology that allows for the use of multimedia and other interactive content online.) These dialers, use your modem secretly to dial long distance numbers, running up charges on your telephone bill.
  
  Some of these dialers operate while you're surfing the internet, disconnecting your dial-up connection to your ISP and reconnecting you through a new, typically international, number. Other forms of this dialer operate when you're away from your computer and leave your system idle for long periods of time.

Why

• These dialers are designed specifically to dial international numbers, earning money for the owner of that international number.
  
  For every minute that a connection is made, the foreign telephone company earns through access fees it charges the originating telephone company, in this case PLDT. The owner of the international number is then compensated through a revenue share agreement with that foreign telco.

Who

• The operators of these dialers are typically located in countries with high toll rates. These include countries in the Caribbean such the Solomon Islands, Diego Garcia, Norfolk Islands and more.
  
  Some larger countries such as the United Kingdom, Hong Kong and even the United Arab Emirates have also been known to host such services.

Preventive Measures

• Typically, these dialers are loaded onto your computer via ActiveX scripts. You should adjust your Internet browser settings to reject ActiveX code, or at the least, warn you when such code attempts to run.
  
  
• However, these software also come as executable programs or straight compiled codes. So when installing software, carefully read the licensing agreement, including the fine print.
  
  
• Turn off your computer when it is not being used.
  
  
• Unplug your phone line from your dial-up modem if you're not using it. Be sure that the volume of your modem is on so that you would hear it if it starts dialing without your consent.
  
  
• Be aware that modem hijacking can also affect internal dial-up modems and fax-modems
  
  
• Always maintain and update your anti-virus, anti-spyware and firewall software. These help in detecting unwanted malicious software.
  
  
• Be aware when visiting web sites of questionable content, or avoid these sites entirely. Do not download from such sites.
  
  
• Monitor your children's use of the Internet. Consider using software the blocks access to such questionable sites.
  
  
• Close pop-up windows by clicking on the "X" button, rather than the embedded buttons.
  
  
• Regularly check your dial-up access numbers for unknown international numbers. Remember that if the number starts with "00", it is probably an international number.
  
  
• Be wary of any unusual icons on your desktop or program files.
  
  
• Do not open e-mails from senders you are not familiar with. Delete these e-mails immediately. Even if you know who the sender is, be wary of executable file attachments.
  
  
• Always activate your DDD security code. This will prevent the programs from successfully dialing international toll numbers. If your phone is not provided with a security code, call 171 and ask how you can have it activated.
  
  
• Consider shifting to broadband internet access (DSL). These services do not use a dial-up modem.
  
  
• There are also software that serve to prevent such modem hijacking. Some of these are offered for free on a trial basis, with licensing fees if you decide to continue using them.
  
  

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