The idea of Icloud storage is only good gallery and Media, passwords private keys and seed phrase or recovery seed shouldn't be store in such places.
I was going through the tweets thread and my mind was a bit scared with things I have been hiding on my Icloud right before I took my privacy serious. So I checked my Icloud and there was an Altcoin wallet I installed back then and ignorant me, I backedup the private key to the Icloud( the developers enable the option backup to my private key to Icloud).
The wallet was no longer on my phone and I decided to installed the app on my device to test the magic. I installed the app, I allowed the face ID and the next thing that pop up was the options to login with my previous account or to import new account. The app had access to my Icloud.
I selected the previous account and that's was how my previous staking transactions pop out, there was no nothing in the wallet as I have already sent them back to an exchange.
I have did one thing with the Icloud backedup private keys....
DELETE The data has been deleted from my cloud. Such things are not meant for any third party, it should only be on your custody, you can mistakenly lose your password to another person, your Apple ID AND PASSWORD will make you loss everything, including privacy once anyone has access to them.
You can see the amount of stolen ethereum that was announced by Metamask, is possible that such exploit is still going on. while Apple has promised you that your data are encrypted,
note anything encrypted can be decrypt.
Stay safe.