Awesome
macOS Lockdown (mOSL)
Bash script to audit and fix macOS Catalina (10.15.x
) security settings
Inspired by and based on Lockdown by Patrick Wardle and osxlockdown by Scott Piper.
Warnings
mOSL is being rewritten in Swift and the Bash version will be deprecated.. See: "The Future of mOSL".
- Always run the latest release not the code in
master
! - This script will only ever support the latest macOS release
- This script requires your password to invoke some commands with
sudo
brew
To install mOSL via brew
execute:
brew tap 0xmachos/homebrew-mosl
brew install mosl
mOSL will then be available as:
Lockdown
Threat Model(ish)
The main goal is to enforce already secure defaults and apply more strict non-default options.
It aims to reduce attack surface but it is pragmatic in this pursuit. The author utilises Bluetooth for services such as Handoff so it is left enabled.
There is no specific focus on enhancing privacy.
Finally, mOSL will not protect you from the FSB, MSS, DGSE, or FSM.
Full Disk Access
Permission
In macOS Mojave and later certain application data is protected by the OS. For example, if Example.app
wishes to access Contacts.app
data Example.app
must be given explicit permission via System Preferences > Security & Privacy > Privacy
. However some application data cannot be accessed via a specific permission. Access to this data requires the Full Disk Access
permission.
mOSL requires that Terminal.app
be given the Full Disk Access
permission. It needs this permission to audit/fix the following settings:
disable mail remote content
disable_auto_open_safe_downloads
These are currently the only settings which require Full Disk Access
.
It is not possible to programatically get or prompt for this permission, it must be manually given by the user.
To give Terminal.app
Full Disk Access
:
System Preferences > Security & Privacy > Privacy > Full Disk Access > Add Terminal.app
Once you are done with mOSL you can revoke Full Disk Access
for Terminal.app
. There's a small checkbox next to Terminal
which you can uncheck to revoke the premssion without entirely removing Terminal.app
from the list.
More info on macOS's new permission model:
Working with Mojave’s Privacy Protection
by Howard OakleyTCC Round Up
by Carl Ashley- WWDC 2018 Session 702
Your Apps and the Future of macOS Security
Verification
The executable Lockdown
file can be verified with Minisign:
minisign -Vm Lockdown -P RWTiYbJbLl7q6uQ70l1XCvGExizUgEBNDPH0m/1yMimcsfgh542+RDPU
Install via brew: brew install minisign
Usage
$ ./Lockdown
Audit or Fix macOS security settings🔒🍎
Usage: ./Lockdown [list | audit {setting_index} | fix {setting_index} | debug]
list - List settings that can be audited/ fixed
audit - Audit the status of all or chosen setting(s) (Does NOT change settings)
fix - Attempt to fix all or chosen setting(s) (Does change settings)
fix-force - Same as 'fix' however bypasses user confirmation prompt
(Can be used to invoke Lockdown from other scripts)
debug - Print debug info for troubleshooting
Settings
See Commands.md
for a easy to read list of commands used to audit
/ fix
the below settings.
Settings that can be audited/ fixed:
[0] enable automatic system updates
[1] enable automatic app store updates
[2] enable gatekeeper
[3] enable firewall
[4] enable admin password preferences
[5] enable terminal secure entry
[6] enable sip
[7] enable filevault
[8] disable firewall builin software
[9] disable firewall downloaded signed
[10] disable ipv6
[11] disable mail remote content
[12] disable remote apple events
[13] disable remote login
[14] disable auto open safe downloads
[15] set airdrop contacts only
[16] set appstore update check daily
[17] set firmware password
[18] check kext loading consent
[19] check efi integrity
[20] check if standard user