Without an authentication bypass, I don't think the CFAA applies (last I perused it).
The end user probably doesn't have standing under CFAA unless the website's ToS suggested they would not act this way. If you, as a web visitor, visit a website you are largely at the mercy of whatever plugins they load onto your browser during that session. In exchange for access to the content on the site, the website owner can steal your data (tracking + analytics), your bandwidth (autoplay advertising videos), and the processing resources associated with loading a webpage (or whatever else you can do in a webpage).
The website's owner might be able to bring a case against the person who injected it, perhaps (depending on who it was and who authorized it). The infraction may not be "breaking into" a computer as the CFAA requires if it was a CBS/Showtime employee/contractor who did it. It is almost certainly grounds for some sort of punitive employment / civil action if it wasn't a requested feature by CBS/Showtime.
The fun part about the law is that the gray areas aren't all defined ahead of time. Web visitors can sue or attempt to bring criminal charges and we get to watch how it unfolds in the courts.