The FBI successfully recovered private Signal messages from a defendant’s iPhone even after the app was deleted. Learn how this security loophole works and the simple setting you must change today to keep your chats private.
Most of us prefer using the Signal app because it is supposed to be very secure with a remarkable end-to-end encryption system that hides our chats from everyone else. It also has a message-disappearing feature to help us set a message deletion time.
But the Federal Bureau of Investigation (FBI) found a way to read private Signal messages on an iPhone, even after the app was deleted. This was revealed in a court case in Texas that these messages can stay hidden in the phone’s memory longer than we expected.
How the loophole works
The case involves a woman named Lynette Sharp and an attack on a Texas detention centre in July 2025. During the trial in April 2026, the FBI revealed they recovered her messages even when she had deleted the Signal app. The bureau, reportedly, retrieved the messages from the iPhone’s push notification database.
During the trial, FBI Special Agent Clark Wiethorn explained how investigators accessed the evidence. When a message arrives, the phone shows a little preview on the screen, which is handled by the phone’s operating system and not the Signal app.
Even if Signal deletes the message later, the phone’s system can save a copy of that preview in its own records. To read these saved messages from Signal, the FBI used Cellebrite, a forensic tool often used by law enforcement to scan seized devices.
A key finding is that the FBI could only see incoming messages, not the ones Sharp sent, which confirms the data came from the notification storage. It shows that while the app’s encryption is strong, the phone’s operating system keeps its own logs of everything.
Are other messaging apps safe?
It is important to note that this isn’t just a problem for Signal, and can happen with any messaging app that shows previews, including WhatsApp or Telegram. Telegram’s founder, Pavel Durov, has openly criticised WhatsApp’s encryption in his recent post on X, calling it a big consumer fraud.
He pointed to a lawsuit claiming that a secret backdoor exists that would allow WhatsApp and Meta, as well as other groups, to bypass the encryption and see private messages.
How to protect your messages
You can stop your phone from storing message previews by changing both your iPhone and app settings.
On your iPhone, go to notification settings for Signal and set Show Previews to Never. Then open the Signal app, go to Settings > Notifications > Notification Content, and select No Name or Content.
Your phone will still alert you when a message arrives, but it will not display or store the text. Without preview data, there is nothing for the system to retain or for forensic tools to extract. Apply the same settings to other messaging apps to avoid exposing message content through notification logs.
