Elcomsoft Phone Breaker can be used
to crack passcodes of encrypted backup files.
You can also use Hashcat.
Terry Maguire, who teaches this class,
did a nice presentation on this that
should be available on the SANS website
where you can see how Hashcat can
be used to crack these backups.
If you want to use Elcomsoft, you go under Tools.
We see Password Recovery Wizard and then Tools.
Under Tools, choose Backup, and navigate out
to the Manifest.plist file.
What it's going to then do-- you say, OK, I want to choose this,
and it shows you a date/time stamp.
You do choose.
The next screen is going to prompt you
on what you want to do.
How do you want to crack that passcode?