This is pretty normal
Work is not an academic environment. When they say "you are doing work for hire" they mean it; it's not "yours" in any sense. The CEO asked your boss to have someone get him some strategy. He chooses you and says "give me some strategy." You send it to him, and he sends it to the CEO. That's pretty normal.
He doesn't want the CEO going directly to you for clarification as it's his role to provide that for his organization. He also doesn't want the CEO to start playing favorites with info he sends him because "Well the last one from PJHar was wrong, now I have one from PJHar, maybe I'll start bothering that manager about reassigning it..."
Your boss is saying "I on behalf of my org is providing you this information." That's a perfectly normal policy. The fact that he is able to forward your work on nearly unchanged means you're doing a really good job. In some cases he is probably altering it, synthesizing it with something another analyst contributed etc. The CEO knows he's not doing it all personally.
However, you do want to make sure you're getting recognition, as part of your ability to improve your career over time. Your boss is valuing you because of what you're providing, but it is fair to want the CEO to maybe know you are the one coming up with a bunch of this good stuff.
Depending on whether you get to interact with both these folks at any time, you can let him know "subtly"... "Hey, glad to see execution around that that strategy around XXX paid off, I worked really hard on that, good work CEO and boss!"
You can also talk to your boss in 1-1s and career planning meetings about "raising your visibility" and "getting exposure across the organization," which are management code words for wanting more folks to know what you're doing. "I'd love opportunities to preset sometime to the C suite," etc. It's entirely possible that he tells the CEO every time they are talking team stuff that "PJHar is my star strategist;" don't assume that he is doing you dirty without any reason. Of course if he is continuously resistant to that then you'll want to try to work around it.