LuLu is an open-source application firewall designed for macOS that monitors and controls outgoing network traffic. It functions by intercepting connection attempts at the system level, allowing users to approve or deny network access for individual programs to prevent unauthorized data transmission.
The software provides granular control over application-level communication, ensuring that only trusted or explicitly permitted software can establish external connections. By maintaining stateful tracking of network flows and validating the cryptographic signatures of requesting binaries, it protects system privacy and prevents malicious software from performing unauthorized data exfiltration or establishing command and control communication.
The system operates through a combination of kernel-level socket filtering and a user-space policy daemon that evaluates connection requests in real time. It is distributed as an open-source utility, providing a transparent interface for managing network security policies and monitoring active outbound traffic on the host operating system.
