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We hear a lot about the Internet of Things, where devices are increasingly connecting to the Internet. However, in addition to these devices being connected to the Internet, they are also increasingly connecting to each other or controlled using various radio frequencies. These radio frequencies often use proprietary or insecure protocols and often damage does not need to be inflicted by intercepting the signals, but simply by blocking them.

Car Lock Jamming

A recent case in Manchester revealed just how fragile our dependence on RF can be. In this example, thieves using a simple car lock jammer, with the intent of breaking into vehicles, caused chaos in a parking lot where nobody could unlock/lock their remote car locks and ended up triggering a number of alarms in the process.

Car locks in North America operate in the 315MHz range and in Europe and Asia in the 433MHz range. Although signal jammers are illegal in most countries, there are many places that sell these devices usually that jam both frequencies for around $50-$200 depending on range and build quality of the device.

Car Lock Jammer

Dual frequency car jammer (315MHz/433MHz) that operates at a 50 meter range

To mitigate the risks posed by car lock jammers, ensure they you see and/or hear cues your car gives when the lock signal has been received. Manual locks of course are not affected, so if you are overly concerned you can override the remote lock and use manual, but some newer vehicles may not provide this option.

In addition to vehicles home automation and locks operate in the 868MHz range via Zigbee and other proprietary protocols. Even if data is encrypted in these systems, by simply being able to jam and disable these devices a great deal of damage can be done. With the ease of acquiring these devices and the fact that they are highly effective we will continue to see more thieves and traditional crimes turn “high tech” taking advantage of these tools.

Device Jamming & Home Invasion

I hear a lot about people “cutting the cord” stating they are free from their wired line and more disturbing is the fact they brag about this online via social media to the public. This puts people at significant risk, risk that many are not aware of. Potential thieves or home invaders now know a key weakness and if they are even a little smart can have an advantage when they invade your home. Just like car lock jammers, cell phone jammers although illegal are still easy to come by.

Cell phone jammer with 20 meter range
Cell phone jammer with 20 meter range

Cell phone jammers can be purchased online and the sites selling them have ways of shipping them to US residents and other countries, even though they are illegal. Using a cell phone jammer can get you a $20K fine or worse. However if a criminal can buy an unlicensed firearm getting their hands on a cell phone jammer is not difficult.

If a thief or home invader enables one of these devices from outside your home, your phone will no longer be able to get a signal and you will not be able to call any emergency numbers for assistance. Many of these jammers will also disrupt Wi-Fi so all communication can easily be disable inside of a home with the flip of a switch on these devices.

Although more and more people are “cutting the cord” this also raises challenges for traditional alarm systems which rely on land lines. If a land line is cut, this usually triggers and alert at the alarm monitoring station. Nowadays alarms have the option of being wired through an internet connection, or use cellular connections. However, these two newer methods have issues, if the Internet or cellular connection goes down the alarm provider is usually not alerted. A thief can easily cut the Internet connection from outside of a house, and we have seen what is possible with a cell phone jammer.

Many carriers are selling additional home automation and security devices and services ranging from alarm systems, cameras and locks. However, one has to wonder how well these devices and security measures function when a jammer is introduced to the mix, particularly as criminals become more tech savvy. These jammers can also disrupt industrial systems, and given enough power can knock out cell reception for a few blocks, so it is conceivable these types of tactics can not only be deployed by criminals, but expanded into the arsenal of extremist groups as part of an attack.

Jammer Detection

HackRF & PortaPack
HackRF & PortaPack in the field

Mitigating the risks frequency jammers post is not an easy task, as you can’t block the blockers. However, there are ways of detecting the presence of a jammer in a given environment.

Jared Boone of ShareBrained Technologies in Portland, Oregon told me that “using spectrum analyzers which captures and assesses changes in average energy in the fob/dongle car lock spectrum for example could be used”.

Jared has been helping to develop the HackRF platform and developed the PortaPack to make the device easily carried into the field which will be available this year. 

The use of spectrum analyzers is not something mere mortals can deploy with easy and definitely not something law enforcement is capable of deploying widely. However, in industrial control environments and areas of higher security, products such as Fluke’s AirMagnet Spectrum product line can and are being deployed to detect the presence of jammers and other anomalous or unwanted frequencies.

Tripwire University
  • marc

    Cisco clean air is a gold mitigation factor automates and integreated un thé wifi AP. De need to have those feature un home wifi ap…

  • Ken – Good article, good read, and very practical advice we need to get through the end-user public. Interestingly enough it was some years back when one could buy a Casio watch from Argos [UK Store] which could be used to capture, and reply the car lock signal to gain illegal access to said compromised auto.

    We are supposed to live in the age of the IoT [Internet of Things] – what we really need to do is understand the implications of what such a three letter acronym has on society – especially when the acceptance of technology is flying in the air.

  • Yes, the world has changed. It's not just devices that are connected to the Internet and to each other. I think people are connected to both at all times!