SOL-11.1-040490 - The operating system must prevent remote devices that have established a non-remote connection with the system from communicating outside of the communication path with resources in external networks - 'RestrictOutbound connections'

Information

This control enhancement is implemented within the remote device (e.g., notebook/laptop computer) via configuration settings not configurable by the user of the device. An example of a non-remote communications path from a remote device is a virtual private network. When a non-remote connection is established using a virtual private network, the configuration settings prevent split-tunneling. Split-tunneling might otherwise be used by remote users to communicate with the information system as an extension of the system and to communicate with local resources, such as a printer or file server. The remote device, when connected by a non-remote connection, becomes an extension of the information system allowing dual communications paths, such as split-tunneling, in effect allowing unauthorized external connections into the system. This is a split-tunneling requirement that can be controlled via the operating system by disabling interfaces.

Solution

The root Role is required.

Remove net_access privilege from users who may be accessing the systems externally.

1. Create an RBAC Profile with net_access restriction

# profiles -p RestrictOutbound
profiles:RestrictOutbound> set desc='Restrict Outbound Connections'
profiles:RestrictOutbound> set limitpriv=zone,!net_access
profiles:RestrictOutbound> exit


2. Assign the RBAC Profile to a user

# usermod -P +RestrictOutbound [username]

This prevents the user from initiating any outbound network connections.

See Also

https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_SOL_11_SPARC_V2R2_STIG.zip

Item Details

Category: SYSTEM AND COMMUNICATIONS PROTECTION

References: 800-53|SC-7(7), CAT|II, CCI|CCI-000366, Rule-ID|SV-216366r603267_rule, STIG-ID|SOL-11.1-040490, STIG-Legacy|SV-61019, STIG-Legacy|V-48147, Vuln-ID|V-216366

Plugin: Unix

Control ID: dcfca005f324872aa023e72c0a8bd2b011ef3cec37f52f36d321668b46ef76c6