MacOS includes an easy-to-use firewall that can prevent potentially harmful incoming connections from other computers.
To turn it on or off:
- From the Apple menu, select System Preferences.
- When the System Preferences window appears, from the View menu, select Security & Privacy (10.7 and later) or Security (10.6).
- Click the Firewall tab. If the orange padlock icon in the lower left side of the window is closed, click it, and then authenticate with your Mac’s administrator username and password. This will allow you to make changes.
- Click Turn On Firewall (10.7 and later) or Start (10.6) to enable the firewall.
- To disable the firewall in macOS, click Turn Off Firewall (10.7 and later) or Stop (10.6).
Firewall Configuration in macOS
To configure the firewall, click Firewall Options (10.7 and later) or Advanced (10.6). In the window that appears, choose from the following options:
- For the strictest setting, check Block all incoming connections.
- Check Automatically allow signed software to receive incoming connections to allow digitally signed applications access to your network without prompting.
- Click Enable stealth mode to have your computer ignore pings and similar software that attempts to discover your computer.
- Use the plus and minus buttons to add and remove applications from the firewall. When added, you can either allow or block traffic to them.
- Click OK to save your settings.
Company Security Policies on Using Firewalls
A firewall policy defines how your company’s firewalls should handle inbound and outbound network traffic. You firewall information security policy or procedures may need to specify IP addresses or address ranges, protocols, applications, and content types.
To determine what you should include in your firewall policy, you should conduct a risk assessment to develop a list of the types of traffic your company needs and how those should be secured. That including which types of traffic can cross a firewall, under what circumstances.
If you need to comply with an information security framework, you will want to reference their documentation, such as the NIST guidelines on firewall policies.
Companies may also determine that all inbound and outbound traffic that isn’t expressly permitted by their firewall policy should be blocked. That traffic is not necessary for the company.
Simple steps like enabling firewalls can reduce the risk of a cyber attack.
Does your company have a firewall policy and provide instructions for macOS users to enable it?