What is Firewall?
Firewall monitors the network traffic between your Mac and the outside world to help protect you from unauthorized communication and intrusions. This feature is designed to require minimal input from you. To ensure you have protection, all you need to do is keep Firewall enabled and, when prompted, specify whether each network that you connect to is trusted.
Is Firewall a free feature?
Yes. The core Firewall functionality is available in all versions of Avast One. However, the advanced application and connection settings are only available if you have a paid Avast One subscription (Avast One Silver Device Protection or Avast One Gold).
Which macOS versions support Firewall?
Firewall is available on all macOS versions that support Avast One (Apple macOS 10.13.x or later). However, the Smart Mode feature is supported only on Apple macOS 11.x or later versions.
How can I enable or disable Firewall?
We recommend you keep Firewall enabled at all times, unless you need to temporarily disable it for troubleshooting purposes.
For instructions to enable or disable Firewall in Avast One, refer to the following article:
What happens when I connect to a new network?
Each time you connect to a new network, Firewall prompts you to specify if you trust the network. Select the relevant option:
- Turn on your VPN: Enable VPN Secure Connection to connect to the internet with extra security and privacy. This option is recommended when you are connected to a public or unsecured Wi-Fi network.
- Trust this network: The recommended option for a private network, such as your home or work network. When you select this option, the network is marked as a Trusted. Each time you connect to a trusted network, Firewall permits all communication within the network and applies a lower level of security to enable better connectivity.
You can change whether a network is trusted any time. For more information, refer to the following article:
How can I control which apps are allowed to connect to the internet?
For information about managing applications using Firewall in Avast One, refer to the following article:
How can I review or monitor all Firewall activity?
The Traffic history options displays a record of all Firewall activity. To access Traffic history, open Avast One and go to Explore ▸ Firewall ▸ Open Firewall ▸ Settings, then click the View button next to Traffic history.
How can I create or modify advanced Firewall application rules?
Firewall creates application rules each time an application or process starts for the first time. These rules determine how Firewall behaves toward each application or process when it connects to the internet or to another network. Users can set connection rules for each individual app to determine how strictly Firewall monitors any incoming or outgoing communication.
We recommend you only modify your application rules if absolutely necessary. In most cases, Firewall formulates optimal rules without your input.
To configure advanced Firewall application rules:
- Open Avast One and go to
Explore ▸ Firewall. - Click Open Firewall.
- Select Settings, then click the Manage button next to Traffic Rules.
- The Application rules tab lists all your current application rules. The following options are available:
- Create a new rule for an application: Hover your cursor over the selected application, then click
…(the three dots) ▸ + Add rule, enter the relevant parameters, then click Save to confirm. - Reset application rules: Hover your cursor over the selected application, then click
…(the three dots) ▸ Reset rules to remove all rules created for this application, then click Reset to confirm. - Edit an application rule: Click the down arrow next to an application, then hover your cursor over the relevant rule. Click Edit (the pencil icon). Edit the relevant parameters, then click Save to confirm.
- Create a new rule for an application: Hover your cursor over the selected application, then click
How can I create or modify advanced Firewall connection rules?
You can configure Firewall connection rules for a service or an IP address. Based on the connection rules you configure, Firewall allows or blocks the incoming and outgoing network connections.
To configure advanced Firewall connection rules:
- Open Avast One and go to
Explore ▸ Firewall. - Click Open Firewall.
- Select Settings, then click the Manage button next to Traffic Rules.
- The Connection rules tab lists all your current application rules. The following options are available:
- Create a new rule for a connection: Click + Add and enter the relevant parameters, then click Save to confirm.
- Remove a connection rule: Hover your cursor over the relevant rule and click the
Xicon to delete it. - Edit a connection rule: Hover your cursor over the relevant rule and click Edit (the pencil icon). Edit the relevant parameters, then click Save to confirm.

