"Broken" is correct, but arguably too strong of a term. It is a man-in-the-middle attack, where the "man" in the middle is relaying the signals without modific

"Broken" is correct, but arguably too strong of a term. It is a man-in-the-middle attack, where the "man" in the middle is relaying the signals without modification and with an extremely short delay between the "key" and the car. The article notes that their system specifically delays the challenge/response by nanoseconds vs. milliseconds by staying in the analog realm because doing a A/D -> Tx -> Rx -> D/A sequence added too much delay. This implies either the car security system either measures the challenge/response delay or could measure it in which case this MitM attack still will work since attack's nSec delays will be very difficult to detect. Most relay attacks require the signals to be converted from analog to digital and back, which takes time. The researchers were able to keep the signals in analog format, which reduced their delay from microseconds to nanoseconds and made their attack more difficult to detect.