12.4: Deny Communication Over Unauthorized Ports
CSF v1.1 References:
PF v1.0 References:
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
Deny communication over unauthorized TCP or UDP ports or application traffic to ensure that only authorized protocols are allowed to cross the network boundary in or out of the network at each of the organization’s network boundaries.
[csf.tools Note: For more information on the Critical Security Controls, visit the Center for Internet Security.]