Security vulnerability on U.S. trains let anyone activate the rear car's brakes

tomshardware.com

12 points·Stratoscope··3 comments

It’s not the brakes on the rear car, it’s doing an emergency brake of the entire train from the last car. It dumps the brake line that runs through the length of the train.

This is part of the train safety system, if the brake line is broken, if cars pull apart, then the brakes on all cars are activated.

Doing this from the rear of the train is less desirable than from the front, as it could possibly pull the train apart as braking travels up the length of the train.

This used to be one of the reasons for having a caboose on the end, with people in it. They could activate the emergency brakes if for some reason it didn’t work from the front.

Conversely, emergency brake from the rear is better in an empty train since otherwise braking propagating from the front can cause run-in which can lift up empty wagons and derail them. Not good on curves.

The right attack could probably cause both the lead and rear to trigger a brake application.

Also, this assumes a pure air brake train - throw ECP in there and it will propagate the brake signal functionally instantly.

I do also wonder whether you could DoS it until the lead loco registers a comms loss and brakes thinking it's lost the last wagon.

If they want to cause real chaos, they should find a way to poke at the distributed power comms protocol. I've no idea whether that's similarly security-through-obscurity.

If this kind of topic interests you, check out what the EU is doing with smart couplers.

Reply on news.ycombinator.com