Editing FileVault (section)

===Master passwords and recovery keys===
When FileVault 2 is enabled while the system is running, the system creates and displays a recovery key for the computer, and optionally offers the user to store the key with Apple. The 120 bit recovery key is encoded with all letters and numbers 1 through 9, and read from {{mono|/dev/random}}, and therefore relies on the security of the [[Pseudorandom number generator|PRNG]] used in macOS. During a cryptanalysis in 2012, this mechanism was found safe.<ref name=choudary2012>{{cite journal|last=Choudary|first=Omar|author2=Felix Grobert |author3=Joachim Metz |title=Infiltrate the Vault: Security Analysis and Decryption of Lion Full Disk Encryption|date=July 2012|url=http://eprint.iacr.org/2012/374|access-date=January 19, 2013}}</ref>

Changing the recovery key is not possible without re-encrypting the File Vault volume.<ref name="aboutfv2" />