MIT Technology Review published a piece on the the problems facing our traffic infrastructures with regards to hacking:
Although the road agency responsible for implementing the system has never faced serious computer security threats, the possibility will become more worrisome as transportation authorities and car makers test new ways for infrastructure and vehicles to communicate in order to reduce congestion and accidents (see “The Internet of Cars Is Approaching a Crossroads”).
“They need to be worrying about this and think about security—it needs to be one of their top priorities,” says Branden Ghena, a graduate student who worked on the project. “It’s hard to get people to care about these things in the same way that it’s hard to get people to change their passwords.”
Wirelessly networked traffic lights have four key components. There are sensors that detect cars, controllers that use the sensor data to control the lights at a given intersection, radios for wireless communication among intersections, and malfunction management units (MMUs), which return lights to safe fallback configurations if an “invalid” configuration occurs. For example, if somehow every light at an intersection is green, the system might fall back to having them all become flashing red lights.
The Michigan researchers found that anyone with a computer that can communicate at the same frequency as the intersection radios—in this case, 5.8 gigahertz—could access the entire unencrypted network. It takes just one point of access to get into the whole system.