The Dangers of Spyware Dialers 

A spyware dialer is a malicious program that installs itself onto a computer and attempts to dial telephone lines at other locations, often incurring expensive phone bills for the victim.  A dialer is much different than the spyware typically bundled with free software downloads.  They are however, difficult to detect and furthermore prove that the dialer is responsible the chargers.  It is also difficult to distinguish a legitimate dialer from a spyware dialer, a factor that has made this infection much harder to control.   

How a Dialer Functions

Any computer system with little or improper security implementations is vulnerable to a spyware dialer.  The Microsoft Internet Explorer Browser is often targeted by this program as it's default settings allow for an easy installation.  This type of spyware can also be installed through applications downloaded from the web, through cookies used to connect you to a site, or pop-up advertisements asking you to install or click something.  Dialers have also been known to "piggyback" on spam carrying pornographic content.  In rare cases, merely viewing an email enables a dialer to be installed. 

Dialers are most commonly distributed when ActiveX security settings are not properly configured in the Internet Explorer web browser.  When the browser loads a page composed by the dialer's creator, a corrupt Active X control is installed which then downloads and runs the spyware program.  Once it has been executed, the dialer is often set to load when the computer starts up.  When the code is loaded into memory, it can wait for the computer to sit idle for a certain amount of time while the user is away.

Similar to most spyware, a dialer is typically installed without the user's knowledge.  When it decides to strike, the program then dials up telephone numbers in foreign countries or to pornographic services, accumulating various charges.   The spyware does this by hijacking a user's internet connection and secretly routing the victim through toll numbers that may cost unknown amounts of money per minute. 

Popular Dialers        

Dialers have been used by pornographic dealers more recently.  This involves covertly downloading and installing a program on the computer of an unsuspecting user, forcing them to automatically dial pay-per view porn sites, charging the victim an outrageous fee each time it occurs. 

A similar exploit uses a well known program called a TIBS dialer, which hijacks a phone modem and redirects it to a pornographic pay-per minute site. 

Another program that has inflicted a considerable amount of damage is the Trojan horse dialer.  This typically comes in the form of a Windows executable file with a filename extension such as EXE., COM., BAT., SCR., PIF., or .BAT.  The Trojan disguises itself as a useful program but actually has intentions of infecting your system.  Once activated, it installs a dialer that manipulates your internet connections, install other types of malware or sends personal data to another location. 

The best defense against any type of dialer is a reliable firewall program.  When configured properly, this application will keep hackers out of your system and spyware dialers away from your phone lines.