Looking for an easy way to hack into your phone? Simply ask Siri to help you.
If you haven’t already done so, it’s time to disallow Siri from your lockscreen. By default, and despite the phone being locked, Siri will cheerfully dispense the answers to such questions as, “What’s my address?” and “Text so-and-so”.
The following article from Naked Security provides more details:
You can adjust the default and prevent unauthorized access to your phone by performing the following steps (if your passcode lock is currently turned off, then you won’t have access to these controls. Turn passcode lock on to change these settings):
HOW TO DISALLOW SIRI FROM THE LOCKSCREEN:
1) SETTINGS | GENERAL | PASSCODE LOCK
2) Where it says “Allow access when locked”, turn that OFF.