If someone has access to the target cell phone, such as for example a wife seeking to listen in on her husband's cell phone calls, it is extremely easy to listen in on cell phone calls. Spyware available for free over the Internet can be downloaded and installed on the target phone. From there, it is a simple matter of being notified every time the third-party caller makes or receives a transmission, and then conferencing in to listen in on the conversation (without the other peoples' knowledge).
Although eavesdropping on cell phones that cannot be physically accessed beforehand to allow for the installation of host spyware is not quite as simple, it is still shockingly much easier than most people realize. At a December 2009 hackers conference in Berlin, Germany, a University of Virginia doctoral graduate showed how loopholes in cell phone smart chips could be exploited.
Many cell phone providers rely on Global System for Mobile Communications technology, or GSM for short. By breaking down the encryptions used by the GMS system to protect each call, the expert was able to eavesdrop on calls all over the world. Since this time, improvements have been made to the GMS technology. But when the revelations were made at the conference, spanning a compilation of data from August 2009 through the end of that year, it sent shock waves through the cell phone industry.
The extent to which cell phone technology can be twisted and undermined by ingenious third parties is constantly making headlines. In the fall of 2011, the website SpyDialier.com was launched so that people who wanted to associate a cell phone number and incoming voicemail message could do so without actually calling the number.
This is a relatively minor aspect of the larger, ongoing problem of cell phone call breaches. Still, many consumers were alarmed that someone could so easily create a tool whereby their cell phone voicemail message could be eavesdropped via the Internet.