Smartphone Security: You'll Never Guess Who Just Messaged You

However, when trusted apps are installed, they often demand all sorts of privileged access. And if they're malicious, there's no way to protect against them. Except that they get reported to Google/Apple and become unavailable. But that doesn't help people who already got pwned.

What am I missing?

Just another thing to be paranoid about in modern life.

So for me that's a non-story.

While I agree that access to contacts should be read-only, and write access should be a special permission, for me it appears to be not a problem. While I have a few other apps installed, most didn't ask for contacts permission (i.e. all games), and from those that did ask, I denied in some cases where it didn't make much sense (why should twitter access my contacts? to find my friends on twitter? I don't need that.)

I actually like the way iOS handling the permissions. The privacy overview in the settings is very easy to understand and maintain. Permissions are only asked once when access to them is actually required in that moment (like when you tap on "take photo" in some app). Permission is not asked for while the app is launching (aside of push notifications and location).

So on iOS usually what happens is this:

    - I install some app, lets say WhatsApp
    - I launch it, it asks for push notifications and contacts permission
    - i use the app
    - if i dont share my location, i'll never get asked for the permission to GPS
    - if i use "send photo" - it will ask for access to photos, but not to the camera
    - sometimes, months or years after usage, it will ask me for a permission, i.e. microphone, because I have never used that feature before and only now want to use it
    - etc.

Don't expect goodwill or good behavior when the fundamental incentives are surveillance and hoovering user data. The multi billion dollar ad economy is based on this.

A system designed with user privacy would be designed to lock down hard on contacts, sms, location, and other personally identifying information access. But the android permission system for instance is so involved it's not surprising lay people are not able to understand the implications, read between the lines of actual motivations and take proper actions.

Facebook does not need your location, contact or sms information. Neither does Google. Yet Google insists on creepily telling you your location on every Google search. This itself is sinister and attempts to normalize stalking behavior.

Uber and others don't strictly need location access, you can type it in, and if required it should be used for the convenience it offers - you are paying for the service - without the possibility of Uber and others collecting historical location and ride information to build invasive files on their users.

Unlike the OP, the attacker can't receive replies from the recipient.

The best heuristic would probably be the contact that has messaged you {first|second|third} most frequently in the last week.

And make an indicator in the status bar similar to how an app recently checked your location.

They might even highlight (in red) new changes in the Contacts app. Or when you get such a message from a new user, the Messages app would do the highlight the first time.

Seems that would mitigate this particular thing.

The current Apple system is slightly better: when the app asks to use one capability (camera, smartphone, contacts) the user is prompted to Grant permission the first time this capability is requeated by the app.

This approach should be further developed with prompt dialogs to continue allowing the app to use the requested capabilities.

Examples:

The App XYZ is requesting read and write access to your contacts. It was granted access on {date} and has read 224 phone numbers, 121 names and 56 addresses and modified two contacts.

Continue allow access? Disallow? Report?

App XYZ is requesting access to microphone. In the last month it accessed and recorded 342 hours of microphone.

Continue allow access?Disallow? Report?

App XYZ is accessing your geolocation in the background. Permission was granted on XXX. During the last month it accessed to your geolocation approximately 461 times every day.

Continue allow access?Disallow? Report?

Apple Goole and others don't have to get on the way of every users all the time with these prompts. They can identify at which time to show this prompt based on analytics (how many users already reported this app etc). They can also identify users who are more privacy aware and that will be glad to read carefully these dialogs and report wrongdoing, and send more prompts to these users.