Hacking cars in JavaScript (Running replay attacks in the browser with the HackRF)

A couple of years ago, I built a project using the RTL-SDR to get live raw data from passing airplanes, in the browser. As I wanted to explore more using Software-Defined Radios, I bought a HackRF One device that can both receive and transmit data, and I downloaded Universal Radio Hacker to start playing around with it. After tinkering a little bit, I had a hunch that it would probably be possible to recreate a similar tool in the browser, all in JavaScript, so I spent time doing just that! .