Skip to content

Instantly share code, notes, and snippets.

@ao
Forked from nathany/decode_firmware_pwd.py
Created September 30, 2018 16:54
Show Gist options
  • Save ao/eef2d3d6de4b6a3b8b70c533be121a87 to your computer and use it in GitHub Desktop.
Save ao/eef2d3d6de4b6a3b8b70c533be121a87 to your computer and use it in GitHub Desktop.
Decode Mac Open Firmware Password
# I forgot the firmware password on my MacBook Air and didn't want to take it in:
# http://support.apple.com/kb/TS2391
# info
# http://paulmakowski.blogspot.com/2009/03/apple-efi-firmware-passwords.html
# run the following command to retrieve your obfuscated firmware password:
# sudo nvram -p | grep security-password
security_password = "%..."
# take the complement of every second bit:
decode_byte = lambda byte: chr(int(byte, 16) ^ int('10101010',2))
# decode the security password, which contains %-prefixed hex values:
decode = lambda pwd: "".join([decode_byte(x) for x in pwd.split('%') if x != ''])
print(decode(security_password))
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment