It'd be useful if someone at State could inform CISA of the meaning of the term "nation-state", unless CISA is very subtly trying to signal which particular countries these attacks are coming from, since nation-states are a small subset of all countries.
Nation-state actors are just illegal criminal organizations, authorities, backed by governments. Above the law, with large budgets.
I mean, maybe you meant illegal, in the sense that they are not always in clear legal status (e.g, NSA doing illegal things), but I think for the reader "legal criminal organizations" makes more sense to the point.
Another way to write it maybe would be "sanctioned criminal organizations" but that would be confusing with the secondary meaning of sanctioned. Oh language :(