The Arista router must be configured to have all inactive interfaces disabled.

Severity
Group ID
Group Title
Version
Rule ID
Date
STIG Version
lowV-256001SRG-NET-000019-RTR-000007ARST-RT-000150SV-256001r882345_rule2025-02-202
Description
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.
ℹ️ Check
Review the Arista router configuration. Verify the interfaces and sub-interfaces execute the commands "show ip interface brief" and "show interface status". Example of a disabled interface: interface Ethernet 8-10 description The interface is administratively shutdown shutdown If an interface is not being used but is configured or enabled, this is a finding.
✔️ Fix
Delete inactive sub-interfaces and disable and delete the configuration of any inactive ports on the router. Deleting the sub-interface: router(config)#no interface Ethernet8.100 Disabling the interface: router(config)#interface Ethernet 8-10 router(config-if-Et8-10)#shutdown Resetting the interface to the default-configuration: router(config)#default interface Ethernet 8