Remotely Stopping Polish Trains

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Turns out that it’s easy to broadcast radio commands that force Polish trains to stop:...the saboteurs appear to have sent simple so-called “radio-stop” commands via radio frequency to the trains they targeted. Because the trains use a radio system that lacks encryption or authentication for those commands, Olejnik says, anyone with as little as $30 of off-the-shelf radio equipment can broadcast the command to a Polish train­—sending a series of three acoustic tones at a 150.100 megahertz frequency­—and trigger their emergency stop function. “It is three tonal messages sent consecutively. Once the radio equipment receives it, the locomotive goes to [...]