My understanding is that merely accessing a computer, even without authorization, is not illegal under the CFAA, since the various articles in the CFAA typically require additional criteria to apply. This is one of the reasons why scraping is in itself not illegal even though the "host" might consider the access "unauthorized".
By reading the CFAA articles, the way I read them almost none apply since the access was not done to obtain privileged information, purposefully or recklessly cause damage etc... but IMHO articles 4) or 6) can actually apply.
Both require the "intent to commit fraud" though and it's my understanding that's often a point open to interpretation. That's also why scraping, while usually legal, can be illegal if that "intent to commit fraud" is established.
Said that, by reading the CFAA more in detail I do have a revised opinion and while I still think it's not a clear-cut case I do believe there is a fair chance the access was illegal under one of the 2 articles mentioned above.