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FBI used iPhone notification data to retrieve deleted Signal messages

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Re: FBI used iPhone notification data to retrieve deleted Signal messages

#21

On Android, when I use WhatsApp and have notifications for groups turned off, I can still see that they arrive briefly and then get removed (the icon top left vanishes). I wonder often, if this is a way to push all group message content into an unencrypted data trace as well - for the same use case.

If the notification has the data, then yes. It's trivial to create an app that listens to notifications; Samsung even has one themselves called NotiStar that replicates the notification history feature that Android normally has.

Re: FBI used iPhone notification data to retrieve deleted Signal messages

#22
post #7

First, a critical setting for Signal users: "Signal’s settings include an option that prevents the actual message content from being previewed in notifications. However, it appears the defendant did not have that setting enabled, which, in turn, seemingly allowed the system to store the content in the database." Second, how can I see this notification history?

On a Pixel, I can see some history by going to

Android > Settings > Notifications > Manage > Notification History

Re: FBI used iPhone notification data to retrieve deleted Signal messages

#23

There needs to be a bit more "group chat" control in Signal messages, wherein you could enforce certain settings for certain chats regardless of the phone settings. You could have group chats that would enforce not showing more information in the notifications, while others would still allow it.

This feels like it would run against the “I bought my device, I should control how it behaves” line of thinking.

But it would be pretty well in line with the "I trust my contact with this communication, but only if they're not systematically misled to copy it to readily exploitable insecure storage" line of thinking.

Since the purposes of the program are pretty heavy on private communication, I'm inclined to think that takes precedence here, especially considering the consequences for dropping default message previews versus adding default reveal of supposedly private information.

Re: FBI used iPhone notification data to retrieve deleted Signal messages

#24

Settings > Notifications > Notification Content > Show: "Name Only" or "No Name or Content" I've had this enabled to prevent sensitive messages from appearing in full whilst showing someone something on my phone, but I guess this is an added benefit as well.

Fwiw, in my Signal app on Android this setting is in

Settings > Notifications > Messages > Show

Re: FBI used iPhone notification data to retrieve deleted Signal messages

#25
post #7

First, a critical setting for Signal users: "Signal’s settings include an option that prevents the actual message content from being previewed in notifications. However, it appears the defendant did not have that setting enabled, which, in turn, seemingly allowed the system to store the content in the database." Second, how can I see this notification history?

On android there are apps that let you see the history - i use NotiStar occasionally to see if i unwittingly dismissed important notifications. And i believe there are apps/settings that help you clear the history from the device.

But this is a reminder that these centralized notification infrastructure (FCM and APNs) store notification content (if the app is told to send content in it - signal with option enabled wouldn't send content) even if we clear local history these middleman still hold it

Re: FBI used iPhone notification data to retrieve deleted Signal messages

#27

Settings > Notifications > Notification Content > Show: "Name Only" or "No Name or Content" I've had this enabled to prevent sensitive messages from appearing in full whilst showing someone something on my phone, but I guess this is an added benefit as well.

I guess enabling Lockdown mode might avoid this particular issue too, together with a bunch of other stuff?

Re: FBI used iPhone notification data to retrieve deleted Signal messages

#28

Settings > Notifications > Notification Content > Show: "Name Only" or "No Name or Content" I've had this enabled to prevent sensitive messages from appearing in full whilst showing someone something on my phone, but I guess this is an added benefit as well.

Just to clarify, this is within the Signal app settings—not the OS (iOS or Android) system settings.

Critical distinction, as merely changing OS notification settings will simply prevent notification content from being displayed on-screen.

Re: FBI used iPhone notification data to retrieve deleted Signal messages

#30
I thought Signal didn’t show message previews by default and you had to go in and enable it? I’ve never had message previews in my Signal and I don’t remember changing anything. Maybe when they introduced the feature, you could pick but they strongly suggested it not showing?
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