iPhone allows access to telephone app and address book despite passcode lock

Users can get around a passcode by using the emergency call function and the lock button. A flaw in the security of Apple iPhones allows a third party to access the list of calls received and made, dial any number and access saved voice mail messages, photo galleries and the entire address book. The address book can also be used to send emails and picture and text messages. The telephone app can easily be launched on an iPhone which appears to be locked against third party access, without requiring the four-digit or alphanumeric pass code.

A vulnerability in the passcode lock makes gaining unauthorised access child's play. On being asked for the passcode, a hacker can simply access the emergency call function and enter any arbitrary phone number, followed by call, then immediately by standby. This launches the telephone app, allowing the hacker to access 'protected' data as described above.

The vulnerability was discovered by a MacRumors forum member and affects the iPhone running iOS 4.1 and apparently iOS 4.0.x. According to initial reports, the vulnerability is fixed in the current beta of the next iOS version – iOS 4.2, which is scheduled for release in November. No workaround is available at present. Apple fixed a previous security vulnerability in the passcode lock in iPhone OS 2.0.x within two weeks of disclosure.

(crve)