I assume you are referring to End to End Encrypted (E2EE) messaging apps here. I’m no programmer/developer/software engineer and I’ll be the first to admit that I don’t know a ton about how most apps work on the backend. That being said, my understanding is that E2EE apps decrypt whatever is being transmitted to them when they get to your device (assuming phone here) (of course it would decrypt it, otherwise how would you make sense of the information?). Once the data is on your phone, it is decrypted. From what I understand, sandboxing apps is not all that robust on Android (at least on “mainstream” versions)
Therefore, the data that was Encrypted from End to End was decrypted at the End and therefore accessible by other applications and processes on your phone. Unless Android sandboxing has improved greatly in the last few weeks.
You’re right that the e2ee part is only about protecting the data while in transit, but that is because it’s the hardest part. Apps can also store the data in an encrypted format so that other apps won’t be able to read it.
I assume you are referring to End to End Encrypted (E2EE) messaging apps here. I’m no programmer/developer/software engineer and I’ll be the first to admit that I don’t know a ton about how most apps work on the backend. That being said, my understanding is that E2EE apps decrypt whatever is being transmitted to them when they get to your device (assuming phone here) (of course it would decrypt it, otherwise how would you make sense of the information?). Once the data is on your phone, it is decrypted. From what I understand, sandboxing apps is not all that robust on Android (at least on “mainstream” versions)
Therefore, the data that was Encrypted from End to End was decrypted at the End and therefore accessible by other applications and processes on your phone. Unless Android sandboxing has improved greatly in the last few weeks.
Applications like signal are encrypted at rest on your device as well - https://security.stackexchange.com/questions/277330/how-does-signal-protect-data-on-the-device-from-unauthorized-access
You’re right that the e2ee part is only about protecting the data while in transit, but that is because it’s the hardest part. Apps can also store the data in an encrypted format so that other apps won’t be able to read it.