OpenSnitch

OpenSnitch is an interactive application-level firewall for GNU/Linux systems inspired by macOS's Little Snitch, providing real-time visibility and control over outbound network connections made by every application. It intercepts connection attempts at the process level and presents the user with a popup dialog to allow, deny, or create persistent rules for each application's network activity. Security-conscious users, malware analysts, and privacy advocates use OpenSnitch to detect unauthorized network communication, identify data exfiltration attempts, and enforce strict application-level network policies. The tool features a Qt-based GUI with connection logging, traffic statistics, and rule management, making it invaluable for monitoring suspicious software behavior and ensuring that only authorized applications communicate over the network.