Hacking the Radio, and Other Analogue Vulnerabilities

If the signal from your favourite radio station isn’t streaming smoothly to your dial, it may be malicious interference from someone who doesn’t appreciate the program you’re trying to listen to. That’s exactly what happened recently to a number of stations around the world where an individual or group was blocking the transmission of the radio signal to disrupt operations.

First Published 26th January 2017  |  Latest Refresh 11th May 2021

Don't touch that dial.

4 min read  |  Reflare Research Team

Radio Heads

In this research brief, we will look at the recent hijacking of several radio stations to analyse how traditionally analogue technologies may be attacked by modern means.

Standard radio programming is transmitted using electromagnetic waves which modulate either the amplitude (AM) or frequency (FM) of the wave to encode analogue audio data. While the wave is electromagnetic, the underlying technology is comparable to that of a record player. The wave is broadcast in all directions and may be received and decoded by anyone in reach. There is no server, cache, data network, authentication or authorisation.

Therefore, there seems to be no practical method of hijacking a radio station short of broadcasting a different signal on the same frequency with a stronger antenna or taking over the radio station by physical force. Neither of these approaches fits the description of a “cyber attack”.

Nonetheless, radio stations are taken over by hackers virtually every year. How can this be?

To answer the question, we must look at how modern radio stations operate.

The Evolution of Analogue Broadcasting

Before the internet, audio signals to be broadcast were generated in close proximity to the broadcasting tower by either playing back physical media or recording from a microphone. The generated signals were then sent to the tower through a physical cable.

Modern radio studios however are often completely separate units from the physical broadcasting system. Radio programs, whether live or pre-recorded, are prepared in potentially several locations and then relayed in a digital format.

This has many advantages for the station operator. Without a need for physical proximity, studios can be established in convenient locations or split across several while making the finished programming available over the internet and one or several physical broadcasting towers at the same time. Popular radio stations may expand their coverage by acquiring the rights to a frequency in a new region and leasing capacity on a broadcasting tower nearby.

However, this approach also opens radio stations up to cyber-attacks.

While the analogue signal broadcast by the radio tower has no real attack surface, the digital streams of data sent to the towers and the digital equipment used to produce the program do.

The days of having to climb up a tower with a pair of wire strippers and a Discman to get your new single played on mainstream radio may be coming to an end.

In the specific case mentioned above, all affected stations appear to have been using Barix STL devices to relay the audio stream between different locations. If these devices are not properly configured, they allow anyone who knows their IP address to send data to them.

The attackers abused this misconfiguration to send their own programming to the receivers instead of the real programming. The fake programming was then amplified and broadcast by the radio towers.

Similarly, the computers used to make the programs and the network hardware used by studios also offer a number of attack surfaces. If they are taken over, the content of the program may be influenced by attackers in innumerable ways.

A Problem More Widespread Than Many Believe

Much of today’s technology which appears to be analogue is vulnerable in similar ways. Computers have become part of virtually every modern production and management chain and as digital components are introduced into classic enterprises, they are opened up to potential cyber-attacks.

We expect this trend of successful, yet unexpected attacks on targets traditionally considered immune to hacking to continue as more and more systems - from factories to radios to transportation – will continue. As computer technologies continue to integrate with existing broadcast systems, new security exploits will appear.

The responsibility of mitigating these vulnerabilities will ultimately fall back to the developers working within the broadcaster, and system integrators of disparate analogue and digital technologies. However, the accountability of ensuring that broadcasts are secure today and remain so into the future will fall in the lap of station senior management. The reputational damage of having a broadcast hijacked, irrespective of who is to blame, will be the senior management team to fix.

This is yet another example where having trained tech staff continuously thinking through the IT security of the station’s operations will go a long way towards reducing the risk, pain, and fallout of dealing with a hack.

However, this vulnerability is not the only exploit you should address when thinking through the risks associated with bridging your operations across the analogue-to-digital gap. You can save yourself a lot of pain by learning from the mistakes of others who have come before you. Discover how to identify and mitigate risks of numerous related hacking trends by checking out other related Reflare research reports.