I think they're talking about the power itself, rather than the lighting systems. Although modern lighting systems all run over ethernet I've never come across

I think they're talking about the power itself, rather than the lighting systems. Although modern lighting systems all run over ethernet I've never come across an installation that wasn't closed-loop (before moving into software engineering I used to work on lighting at live events). There's a lot of exaggeration in the story. It makes it sound as if the stadium would have been plunged into darkness, when in fact there's significant contingency planning at these type of events around power loss, and there is in nearly all cases a mechanical (rather than computerised) failover. A far more interesting (I think, anyway) would be an attack on the actual lighting control systems themselves. Like I said, they're running over ethernet on a variety of proprietary and not-so proprietary protocols that haven't had much attention on the security side of things. And yes, they're not connected to the internet, but it wouldn't be too difficult to compromise a lighting unit itself before it was shipped from the rental shop to the stadium.