If you want to hack the light into turning green, it might not be as hard as you think. A research team at the University of Michigan found traffic lights in more than 40 states are still running on unencrypted Wi-Fi networks, making them relatively easy to commandeer. Even where networks are encrypted, the devices still suffer from vulnerable debugging ports and default manufacturer logins, which make it easy for an attacker to guess the login and password in advance. On some level, the bad security makes sense — traffic lights are everywhere, and the damage from hacking one is fairly limited — but if the "fastest lap" scene ever finds out about this, we may be in serious trouble.