Not quite, failing to talk to them would be not sending anything, what they're actually doing is much worse. Based on what people have seen it's sending random data to the device. E.G. I send it something like "Hello World" and it sends the device "Launch Nuke". If it actually failed to talk to the device that wouldn't be too bad, it would just look like the chip was defective. What it's doing is massively dangerous because it's basically performing fuzzing on the underlying device and who knows what that might trigger.
> What it's doing is massively dangerous because it's basically performing fuzzing on the underlying device and who knows what that might trigger.
Yes, this exactly. Most of the systems these chips are attached to are tiny embedded processors with very little RAM and no memory protection. It's almost a given that a non-negligible number of these systems will crash on this kind of input. The FTDI chip wouldn't even need to be in a critical signal path if it's spewing garbage all over memory.
