The Security Bypass
By default, the iPhone attempts to make communication as frictionless as possible. If you miss a phone call, iOS places a notification on your lock screen. Conveniently, the operating system enables a feature called “Return Missed Calls,” which allows anyone to simply tap that notification and instantly dial the person back without ever needing to unlock the phone with Face ID or a passcode. While this is helpful if you are driving, it is a massive privacy risk if you leave your phone on a desk. A stranger or a prankster can easily return calls to your contacts from your locked device. You must secure the dialer.
How to Turn Off Return Missed Calls
You can permanently revoke the ability to dial out from the lock screen via the Face ID settings.
- Open the Settings app on your iPhone.
- Scroll down and tap on Face ID & Passcode (or Touch ID & Passcode on older models).
- Enter your device’s PIN code to access the secure menu.
- Scroll down to the section labeled “Allow Access When Locked.”
- Locate the toggle switch labeled Return Missed Calls.
- Toggle this switch to the Off position (the green background will disappear).
Forced Authentication
The change takes effect instantly. The iPhone will completely sever the connection between the lock screen notification banner and the phone’s dialing engine. You will still see the missed call notification on your screen, but if you tap it, the phone will throw a padlock icon and aggressively demand that you unlock the device with your face or passcode before it actually places the outbound call.