According to ShinyHunters, the records contain extensive data on Premium members including email addresses, activity type, location, video URL, video name, keywords associated with the video and the time the event occurred. Activity types include whether the subscriber watched or downloaded a video, or viewed a channel and events include search histories.

This sort of thing is one of those examples why “no log, no profile” service is probably a good idea. The service could have offered the option to charge a fee for access, but not retain customer data. They didn’t do that. At some point down the line, someone got ahold of the data, which I imagine that their customers are not really super keen on having floating around.