Passport id info : is this info targeted by cyber criminals

You mean am airline company app? Sure. There really isn't much tied to your passport number. And the advantages of an electronic boarding pass especially if you are flying with just carryon are sweet.

I am pretty sure in the U.S., most people check in online using an app these days. I always try but sometimes am not able to complete the process and get boarding passes if it’s an international flight. If it’s not safe, we are all compromised. Also, I fly American a lot because of location and my passport info already lives in their system, as does my credit card info.

Your passport number is just that, a number, it has no application other than as an identifier on your passport. Even the other information on the passport is of little use, your birth date being maybe the most sensitive, but hardly confidential.

Even the physical passport has little value to a criminal, more a pain to you if lost or stolen to replace.

So no danger using the number in online forms, for airlines, hotels will ask, some museums will ask for tickets, all very common and safe.

What would they do with check in info? Pick a bad seat for you?

I work in cyber security. Your passport information is useless. You cannot take out a loan apply for a credit card or otherwise do fun activities with a passport number

So, my passport is sort of like my credit score?