Dejan Ornig, a 26 year old student at the University of Maribor’s Faculty of Criminal Justice and Security was recently almost jailed for finding a security flaw in Police TETRA communications in his home country of Slovenia. Back in 2013 his University Computer Science class of 25 was assigned a task to research security vulnerabilities in TETRA. TETRA is a RF digital communications protocol often used by authorities due to its ability to be secured via encryption. During his research he used an RTL-SDR and the open source Osmocom TETRA decoder, and discovered a flaw in the Slovenian Police’s TETRA configuration which meant that encrypted communications were often being broadcast in the clear. Translated, Ornig said:
For $20 I bought a DVB-T receiver (RTL-SDR), on the Internet, I have found also freely available and open-source software OsmoCOM. Free access solution for decoding the signal Tetra eighth-tetra is already prepared in advance programming framework based on the platform GNU.
He goes on to say (translated):
I was even more surprised when I found that most users do not have authentication turned on the radio terminal, even though the Ministry of the Interior in the documents and tenders repeatedly wrote to all the radio terminals to access networks using authentication.
Shortly after discovering the flaw, Dejan privately contacted the authorities with his findings. But after two years of repeatedly contacting them and waiting for a fix, Dejan decided to take his story to a local news agency in February 2015. At this point the Slovenian Police became interested in Dejan, and instead of fixing the problem, decided to conduct a search on his house, seizing his computer and RTL-SDR. After the search the Police made life harder for Ornig by trying to lump on other problems. During the search they found a “counterfeit police badge” in his house and apparently accused him of impersonating a police officer, and after a search of his PC they also decided to charge him after finding out that he covertly recorded his ex-employer calling him an “idiot”.
Ornig has now been given a 15 month suspended jail sentence for attempting to “hack” the TETRA network. Fortunately the suspended part means that in order to not go to jail Ornig simply must not repeat his crime again within 3 years. While SDR’s and radios are not illegal in most countries this is a reminder to professional and amateur security researchers to check that what you are doing is legal in your country. Even if it is for the overall good, Police often do not have the technical competence to understand security researchers and may react illogically to findings. The good news about Ornig’s story is that apart from the suspended jail sentence the authorities appear to have now worked with him to fix the problems.