Premise: What if political activists wanted to prove US anti-terrorism are misguided by faking a new kind of terrorist attack?

Technical stuff: ObCo's system monitors and control warehouse forklifts, trucks, and other vehicles used for storing and transporting foodstuffs around. Each truck is equipped with a small computer that runs ObCo's software and is connected to the controls of the vehicle. The software can be updated over wireless networks. For security purposes, the software must be digitally signed for it to be accepted by the box. Alan's attack is to update the computers with both new software (that prevents vehicles from working) and a new key (so that fixed software can't be updated). To fix this, either ObCo needs to find the new key or they must visit each vehicle and physically reset it and update the key in the computer. There are about a hundred thousand vehicles and fixing each takes about an hour, so it would take weeks to fix them all.