In Apple iPhone devices, passwords to email accounts, Web sites, and certain third-party software are stored securely in keychains that are encrypted with hardware keys unique to each individual device. Prior to the release of iOS 4, keychains remained encrypted with a device-specific key even when exported to an off-line backup file. With iOS 4 this is not necessarily the case.
With the release of Apple’s new OS, iOS 4, the keychains can now be stored in device backups encrypted only with backup’s master password. Knowing the password protecting the off-line backup, it is now possible to gain access to encrypted keychains. The latest version of Elcomsoft iPhone Password Breaker allows to browse the contents of keychains — as noted above, if backup password is known (or has been recovered with EPPB).