This rule aims to detect instances where the system firewalls, specifically 'firewalld', 'iptables', or 'ufw', are disabled on Linux systems. Disabling a system firewall can pose significant security risks as it allows adversaries potential unmonitored access to the network, effectively bypassing the controls that are in place to protect system resources. The detection logic focuses on audit logs, looking for events that correspond to the stopping of these firewall services. By monitoring these events, organizations can be alerted to unauthorized or unexpected firewall deactivations, enabling them to respond promptly and investigate the underlying causes of such actions. This rule is applicable in environments configured with Linux and utilizing 'auditd' for logging service activities.