Little Snitch

From RaySoft

Little Snitch is a host-based application firewall for macOS. It can be used to monitor applications, preventing or permitting them to connect to attached networks through advanced rules.[1]

Unlike a stateful firewall, which is designed primarily to protect a system from external attacks by restricting inbound traffic, Little Snitch is designed to protect privacy by limiting outbound traffic. Little Snitch controls network traffic by registering kernel extensions through the standard application programming interface (API) provided by Apple.[1]

Documentation

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