jazznut1
Level 1
(8 points)
Q: File Vault using same password as user account?
As my computer is password protected is what advantage would there be in using File Vault especially if it is going to have the same password as my user account?
iMac, Mac OS X (10.7.5)
BobHarris
Level 6
(19,272 points)
Password protected ONLY prevents someone from logging into your Mac when it is booted from you boot disk. If it is booted from the recovery partition, they could access your data without your password. If they attach an external bootable disk to your Mac and boot from that, they can access your data without your password. If they remove the disk from your Mac, they can attach it to another computer and read your data.
A FileVault whole disk/partition encrypted Mac, if stolen, cannot be accessed for your data, unless your password is trivial to guess or brute force in a reasonable amount of time (See Password Haystacks <https://www.grc.com/haystack.htm>). If you take your Mac in for repair, and do not give them your password, they cannot read your data (but always backup before doing this as they can erase your storage).
It is still possible for them to erase the disk, but your personal data is not at risk unless you have a trivial password.
In addition, rotational hard disk drives and SSD storage often do things internally that may result in some of your data still being accessible, even after erasing the disk (there are spares that sometimes get used, and the retired sectors might be still readable with the right tools and software). A FileVault encrypted disk means those retired sectors are just random bits without the decryption key.
If you sell your Mac, or hand it down to a friend or relative, all you need to do with FileVault encrypted storage, is reformat the disk, which will throw away the encryption/decryption key, and then you put a clean version of OS X on it, when you sell it or pass it down. All that is left is a bunch of random bits on your disk that they cannot decode.
