V-279597

Discussion

To prevent unauthorized device connection, unauthorized information transfer, or unauthorized tunneling (i.e., embedding of data types within data types), organizations must disable or restrict unused or unnecessary physical and logical ports/protocols on information systems. Operating systems can provide a wide variety of functions and services. Some of the functions and services provided by default may not be necessary to support essential organizational operations. Additionally, it is sometimes convenient to provide multiple services from a single component (e.g., VPN and IPS); however, doing so increases risk over limiting the services provided by any one component. To support the requirements and principles of least functionality, the operating system must support the organizational requirements, providing only essential capabilities and limiting the use of ports, protocols, and/or services to only those required, authorized, and approved to conduct official business or to address authorized quality of life issues.

Check Content

1. Verify Nutanix OS prohibits or restricts using functions, ports, protocols, and/or services, as defined in the PPSM CAL and vulnerability assessments using the following command.

$ sudo iptables -S

2. If IPv6 is in use, run the following command.

$ sudo ip6tables -S

3. Review the site or program PPSM CAL; Verify the services allowed by the firewall match the PPSM Component Local Service Assessment (CLSA). 

If there are additional ports, protocols, or services that are not in the PPSM CLSA, or there are ports, protocols, or services that are prohibited by the PPSM CAL, this is a finding.