Yes Apple has their iCloud key, if you live in China, the key is controlled by the Ccp, potentially dangerous for abuse from lea, highly recommend not to use Apple devices if you live there. The other problem is if they same set of keys for global users that it is possible to crack encryption for global users using the same keys, hence compromising security if one day Ccp want to access to the files of some American’s phone through iCloud.
The only thing it improves is data security which can in some extent resist against identity theft, financial fraud, etc. Does having an eSIM card improve my data security?
Yes, there are significant security benefits. An eSIM card cannot be stolen without stealing the phone, whereas removable SIM cards are sometimes stolen, and used in port out scams. That’s when identity thieves fraudulently swap stolen SIM cards into different phones to gain access to the victim’s calls and text messages. The thieves may then try to reset credentials and gain access to the victim’s financial and social media accounts.
For more information about SIM swapping, port out scams, cell phone cloning and subscriber fraud, see our consumer guide on cell phone fraud. https://www.fcc.gov/consumers/guides/esim-cards-faq
Tutanota first use the user password to generate an AES key using BCrypt, that AES key is then used to encrypt the private key. The encrypted private key and hashed AES key is then sent to the server, hence the server does not store nor know the private key and the hashed AES key is used to authenticate the user. It uses SHA256 for hashing, it’s safe because the hashing algorithm is one way only and not reversible, meaning you can’t convert the hash to the password but only the other way around the password can generate the hash, so even the server is compromised it doesn’t gain access to your password.
Proton Mail uses PGP which depends on which cipher both recipient and sender, sharing PGP keys are also problematic. PGP doesn’t encrypt subject line but Tutanota does. Tutanota uses AES-128 and RSA-2048 for their encryption and uses AES-128 for external encrypted email which Tutanota and Proton Mail also supports.
Jeez not wiping the server