As the title says, some weird load balancers issues, core problem being that user-specific data would be cached and returned to other users.

They detail four cases of this, but they are all largely the same and somewhat random. Cache entry expires, and another users details get cached and start appearing. The last vulnerability was the most interesting as it was a JavaScript file that would call a function to set the users Authorization header. This page would be cached using the loc parameter as a key, so an attacker could craft a page with an arbitrary loc parameter, send it to a victim and get the page cached with their victims authorization headers.