Why is Firewall button disabled?

MacBook Air early 2015 should be running macOS 12 (“Monterey”), as a starting point. Not macOS 10.12 (“Sierra”).

If the Mac has potentially been compromised, the recovery path is a backup or two, an erasure, and a reinstallation, and without restoring apps and without restoring settings. Cleaning up a compromised install—and yes, Macs can absolutely be breached—without a reinstall is somewhere between perilous and exceedingly difficult.

New and robust and unique passwords everywhere, including the password reset paths, and including the cellular carrier account access passcode or PIN particularly if that was saved somewhere.

The firewall itself isn’t a particular issue, though can potentially be used to mask other latent issues. Potentially mask. But not necessarily reliably mask other issues. That’s where the re-install from known-good distributions and not migrating apps and settings. (Docs only, and that’s still somewhat risky with Microsoft Office documents and PDF documents as those can contain executable code; malware, backdoors, etc.)

Markhsw3 wrote:

Thanks Ozzie. Looks like they got her password, changed the phone number for two-factor I.D. and get into her email and social media accounts. She was able to change the phone number back and set new passwords, but it looks like they are back. I found the lock and that may be the problem. This requires re-entering her new password, to which hackers might again gain access. After the firewall is back on --well she is wanting to take some other actions.

If someone got a hold of the password somehow, the device was not hacked. They could not have changed the phone number for the 2FA without a trusted device.

Regardless, the firewall setting had nothing to do with this.

See here:

If you think your Apple ID has been compromised - Apple Support

There are a couple of reasons why the Firewall button might be disabled on your 2015 MacBook Air running Sierra:

1. Admin Permissions: You might not be logged in with an administrator account. The ability to change firewall settings often requires admin privileges. Try logging in with an admin account and see if the button becomes active.
2. Management Software: It's possible that your MacBook Air is being managed by some configuration software, such as one used by a company or school. This software might be controlling the firewall settings and preventing you from enabling it directly.

Here are some things you can try:

• Check Login Account: Switch to an admin account and see if the button becomes active.
• Consult IT (if applicable): If you think your computer is managed by an organization's software, consult your IT department to see if they can adjust the firewall settings for you.
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Important Note: Disabling the firewall weakens your computer's security. Only disable it if you absolutely need to, and only for troubleshooting purposes. If you can't enable the firewall yourself due to management software, consult your IT department to ensure your computer is properly protected.

Ozzie1910 wrote:

Nobody can hack any Apple device ,

That is not true. While Apple devices are quite secure, they are not impregnable.

Nobody can hack any Apple device , did she enable the firewall settings after click on the lock 🔒 to unlock that setting?