My Mac crashed, operating system error, tried reinstalling OS, no luck.... anyway I need to do a fresh install so I am copying my data off the machine using command line and recovery mode.

My question is, I've copied the data without any issues, but isn't this a security flaw?

What's to stop me going to someone's Mac, starting recovery mode, open terminal, go to the Users or a user directory and copy off whatever I want?

  • Well most people lock their Macs with FireVault which scrambles the data unreadable without entering password and even if you boot from an external os to copy the files you can't as the files are encrypted. If you want to lock your Mac with FireVault. Commented Feb 26, 2018 at 10:53
  • Physical access to the Mac but no firmware password/encryption > no IA
    – klanomath
    Commented Feb 26, 2018 at 10:54

1 Answer 1


That is what Filevault is for.

If a bad actor has your computer in their hands you need encryption to keep them out. No encryption, no security.

Even if you have the computer firmware password protected, that wouldn't prevent them removing the drive to access from another machine.

  • So, when I get my mac back installed with a fresh OS I should use filevault. This would prevent people from reading the data that is on the drive through recovery mode? But what happens if I want to read my own data through recovery mode?
    – panthro
    Commented Feb 26, 2018 at 11:12
  • You know the password;)
    – Tetsujin
    Commented Feb 26, 2018 at 11:20
  • With APFS, is FileVault still necessary?
    – samh
    Commented Feb 26, 2018 at 12:21

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