If you're using a Mac with the Apple T2 Security Chip, Startup Security Utility offers three features to help secure your Mac against unauthorized access: Firmware password protection, Secure Boot, and External Boot.

Open Startup Security Utility

1. Turn on your Mac, then press and hold Command (⌘)-R immediately after you see the Apple logo. Your Mac starts up from macOS Recovery.
2. When you're asked to select a user you know the password for, select the user, click Next, then enter their administrator password.
3. When you see the macOS utilities window, choose Utilities > Startup Security Utility from the menu bar.
4. When you're asked to authenticate, click Enter macOS Password, then choose an administrator account and enter its password.

Set a firmware password

By default, Gatekeeper is configured to allow apps from the Mac App Store and from registered developers. Users can make this more or less strict: Open System Preferences. Getting a brand-new MacBook Pro can be an exciting thing, but before you dive right in, there are a few settings that you should change first. These can help tweak your Mac to perfection, making. Next, you will be guided through the steps necessary to install security on your Mac. Click on Continue. In order to continue the installation, you will have to agree to the terms of the software Subscription Agreement. Select the disk where you want to install the Bitdefender software, then click on Continue. After that, select Install.

You can use a firmware password to prevent anyone who doesn't have the password from starting up from a disk other than your designated startup disk. To set a firmware password in Startup Security Utility, click Turn On Firmware Password, then follow the onscreen instructions. Learn more about firmware passwords.

You can also change your external boot setting to prevent even those who know the firmware password from starting up from external media.

[Moved here from HT208330] Change Secure Boot settings

Use these settings to make sure that your Mac always starts up from a legitimate, trusted operating system.

Full Security

Full Security is the default setting, offering the highest level of security. This is a level of security previously available only on iOS devices.

During startup, your Mac verifies the integrity of the operating system (OS) on your startup disk to make sure that it's legitimate. If the OS is unknown or can't be verified as legitimate, your Mac connects to Apple to download the updated integrity information it needs to verify the OS. This information is unique to your Mac, and it ensures that your Mac starts up from an OS that is trusted by Apple.

If FileVault is enabled while your Mac is attempting to download updated integrity information, you're asked to enter a password to unlock the disk. Enter your administrator password, then click Unlock to complete the download.

If the OS doesn't pass verification:

• macOS: An alert informs you that a software update is required to use this startup disk. Click Update to open the macOS installer, which you can use to reinstall macOS on the startup disk. Or click Startup Disk and choose a different startup disk, which your Mac will also attempt to verify.
• Windows: An alert informs you that you need to install windows with Boot Camp Assistant.

If your Mac can't connect to the Internet, it displays an alert that an Internet connection is required.

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• Check your Internet connection, such as by choosing an active network from Wi-Fi status menu in the menu bar. Then click Try Again.
• Or click Startup Disk and choose a different startup disk.
• Or use Startup Security Utility to lower the security level

Medium Security

During startup when Medium Security is turned on, your Mac verifies the OS on your startup disk only by making sure that it has been properly signed by Apple (macOS) or Microsoft (Windows). This doesn't require an Internet connection or updated integrity information from Apple, so it doesn't prevent your Mac from using an OS that is no longer trusted by Apple.

If the OS doesn't pass verification:

• macOS: An alert informs you that a software update is required to use this startup disk. Click Update to open the macOS installer, which you can use to reinstall macOS on the startup disk. This requires an Internet connection. Or click Startup Disk and choose a different startup disk, which your Mac will also attempt to verify.
• Windows: An alert informs you that you need to install windows with Boot Camp Assistant.

No Security

No Security doesn't enforce any of the above security requirements for your startup disk.

Change External Boot settings

Use this feature to control whether your Mac can start up from an external hard drive, thumb drive, or other external media. The default and most secure setting is ”Disallow booting from external media.” When this setting is selected, your Mac can't be made to start up from any external media. Attempting to do so will cause your Mac to display a message that your security settings do not allow this Mac to use an external startup disk.

To allow your Mac to use an external startup disk:

1. Open Startup Security Utility.
2. Select ”Allow booting from external media.”
   Your Mac doesn't support booting from network volumes, whether or not you allow booting from external media.
3. If you want to select an external startup disk before restarting your Mac, quit Startup Security Utility, then choose Apple menu  > Startup Disk.

We design Mac hardware and software with advanced technologies that work together to run apps more securely, protect your data, and help keep you safe on the web. And with macOS Big Sur available as a free upgrade, it’s easy to get the most secure version of macOS for your Mac.*

Apple M1 chip.
A shared architecture for security.

The Apple M1 chip with built-in Secure Enclave brings the same powerful security capabilities of iPhone to Mac — protecting your login password, automatically encrypting your data, and powering file-level encryption so you stay safe. And the Apple M1 chip keeps macOS secure while it’s running, just as iOS has protected iPhone for years.

Apple helps you keep your Mac secure with software updates.

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The best way to keep your Mac secure is to run the latest software. When new updates are available, macOS sends you a notification — or you can opt in to have updates installed automatically when your Mac is not in use. macOS checks for new updates every day and starts applying them in the background, so it’s easier and faster than ever to always have the latest and safest version.

Protection starts at the core.

The technically sophisticated runtime protections in macOS work at the very core of your Mac to keep your system safe from malware. This starts with state-of-the-art antivirus software built in to block and remove malware. Technologies like XD (execute disable), ASLR (address space layout randomization), and SIP (system integrity protection) make it difficult for malware to do harm, and they ensure that processes with root permission cannot change critical system files.

Download apps safely from the Mac App Store. And the internet.

Now apps from both the App Store and the internet can be installed worry-free. App Review makes sure each app in the App Store is reviewed before it’s accepted. Gatekeeper on your Mac ensures that all apps from the internet have already been checked by Apple for known malicious code — before you run them the first time. If there’s ever a problem with an app, Apple can quickly stop new installations and even block the app from launching again.

Stay in control of what data apps can access.

Apps need your permission to access files in your Documents, Downloads, and Desktop folders as well as in iCloud Drive and external volumes. And you’ll be prompted before any app can access the camera or mic, capture keyboard activity, or take a photo or video of your screen.

FileVault 2 encrypts your data.

With FileVault 2, your data is safe and secure — even if your Mac falls into the wrong hands. FileVault 2 encrypts the entire drive on your Mac, protecting your data with XTS-AES 128 encryption. Mac computers built on the Apple M1 chip take data protection even further by using dedicated hardware to protect your login password and enabling file-level encryption, which developers can take advantage of — just as on iPhone.

Designed to protect your privacy.

Online privacy isn’t just something you should hope for — it’s something you should expect. That’s why Safari comes with powerful privacy protection technology built in, including Intelligent Tracking Prevention that identifies trackers and helps prevent them from profiling or following you across the web. A new weekly Privacy Report on your start page shows how Safari protects you as you browse over time. Or click the Privacy Report button in your Safari toolbar for an instant snapshot of the cross-site trackers Safari is actively preventing on that web page.

Automatic protections from intruders.

Mac Pro Change Security Preferences To Allow App Installation Windows 10

Safari uses iCloud Keychain to securely store your passwords across all your devices. If it ever detects a security concern, Password Monitoring will alert you. Safari also prevents suspicious websites from loading and warns you if they’re detected. And because it runs web pages in separate processes, any harmful code is confined to a single browser tab and can’t crash the whole browser or access your data.

Find your missing Mac with Find My.

The Find My app can help you locate a missing Mac — even if it’s offline or sleeping — by sending out Bluetooth signals that can be detected by nearby Apple devices. These devices then relay the detected location of your Mac to iCloud so you can locate it. It’s all anonymous and encrypted end-to-end so no one — including Apple — knows the identity of any reporting device or the location of your Mac. And it all happens silently using tiny bits of data that piggyback on existing network traffic. So there’s no need to worry about your battery life, your data usage, or your privacy being compromised.

Keep your Mac safe.
Even if it’s in the wrong hands.

Mac Pro Change Security Preferences To Allow App Installation System

All Mac systems built on the Apple M1 chip or with the Apple T2 Security Chip support Activation Lock, just like your iPhone or iPad. So if your Mac is ever misplaced or lost, the only person who can erase and reactivate it is you.