Title

The router must be configured to have all inactive interfaces disabled. (Cat III impact)

Discussion

An inactive interface is rarely monitored or controlled and may expose a network to an undetected attack on that interface. Unauthorized personnel with access to the communication facility could gain access to a router by connecting to a configured interface that is not in use. If an interface is no longer used, the configuration must be deleted and the interface disabled. For sub-interfaces, delete sub-interfaces that are on inactive interfaces and delete sub-interfaces that are themselves inactive. If the sub-interface is no longer necessary for authorized communications, it must be deleted.

Check Content

Review the router configuration. If an interface is not being used but is configured or enabled, this is a finding.

Fix Text

Delete inactive sub-interfaces and disable and delete the configuration of any inactive ports on the router.

Additional Identifiers

Rule ID: SV-207112r604135_rule

Vulnerability ID: V-207112

Group Title: SRG-NET-000019

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.