9.4: Apply Host-Based Firewalls or Port-Filtering
CSF v1.1 References:
PF v1.0 References:
Threats Addressed:
The next version of the control set incorporates all or part of this control into: 4.4: Implement and Manage a Firewall on Servers, 4.5: Implement and Manage a Firewall on End-User Devices.
Control Statement
Apply host-based firewalls or port-filtering tools on end systems, with a default-deny rule that drops all traffic except those services and ports that are explicitly allowed.
[csf.tools Note: For more information on the Critical Security Controls, visit the Center for Internet Security.]