A Simple Email Message Can Crash the Mail App Due to the iOS 16 ‘Mailjack’ Bug

If you updated your iOS 16 to the latest version, your device may be vulnerable to a specially crafted email that will cause your Mail app to crash.

The mail message itself will look completely ordinary; however, the sender field will have a certain number of special characters. These extra characters are the thing that is caused the Mail app to malfunction, preventing any access it. The bug itself was dubbed “Mailjack” and unless the issue is going to be patched soon, anyone will be able to use it to lock other people out of their email accounts.

The email that was causing the crash was first discovered by Equinux. Normally, any letter contains the email address from where it was sent which looks something like this: From: [email protected]. The malicious letter contains symbols instead of letters and numbers: From: “”@gmail.com.

All of the major email services have protection against such a simple attack, allowing them to rewrite and filter inbound emails with weird syntax preventing their apps from crashing. Apple, on the other hand, doesn’t have such protection in its iCloud Mail, making it easy prey for such an attack.

Currently, the only solution to this problem is using an older version of iOS to enter your mailbox and delete all the malicious messages from the inbox, spam folder, and trash folder. Simply moving the email to another folder doesn’t work, since as soon as you enter this folder using your original device, the app will crash once again.

Does it surprise you that Apple doesn’t have protection against such simple attacks, while Google and other major mail services do? When do you think this bug will be fixed? Tell us in the comment section below.