But how do you hack a walk signal? City officials said they fell victim to a common mistake: Failing to change the default password.

“These crosswalk push-buttons were newly installed,” explained public works spokesperson Nancy Kuhn in a statement to Denverite and other media.

The devices were “still bagged and with their factory settings,” including a default password “that we now have learned is easy to find online.” The push-buttons weren’t meant to be turned on yet, but had recently been connected to power.