Big headline, luckily not as scary as it looks, but an important lesson...

The way it works: The FBI had physical access to the device and used forensic extraction software. When Signal messages arrive, iOS stores push notification previews locally on the device. Those previews stayed behind even after Signal was uninstalled.

Two things:
- Only incoming messages were captured this way
- Disappearing messages that had already vanished inside Signal were still recoverable from the notification cache

This is iOS behavior, not a Signal vulnerability. And likely impacts other apps.

This is a very high threat model concern, though the fix is straightforward:
Signal → Settings → Notifications → Show → set to "No Name or Content"

You'll still get a notification ping, but iOS just won't cache anything useful.

Notifications in general are a pretty interesting privacy/security attack vector in general, as they're largely managed by Apple & Google.

We cover this and a lot more in our Signal hardening guide for those who want to learn all the ins/outs: https://youtu.be/DPjg3651oJM

Lock Down Signal Messenger: Ultimate Hardening Guide

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FBI Extracts Suspect’s Deleted Signal Messages Saved in iPhone Notification Database

The case was the first time authorities charged people for alleged “Antifa” activities after President Trump designated the umbrella term a terrorist organization.

404 Media
@techlore
I think Signal addressed this a long while ago.
@draken @techlore I believe the part that isn’t an issue is Apple or Google having the content of your messages (or who you’re messaging) via push notifications. This article talks about notification logs apparently being extracted from the device itself.
@oliviablob @techlore
The part that is the push notifications is certainly part of it and Signal already addressed that part: Disable the push service to read the message within the app. That should also eliminate the on-device logs through the iToy.
Lock Down Your Signal: Ultimate Hardening Guide

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