NET-VLAN-002 - Disabled ports are not kept in an unused VLAN.
Disabled switch ports must be placed in an unused VLAN (do not use VLAN1). It is possible that a disabled port that is assigned to a user or management VLAN becomes enabled by accident or by an attacker and as a result gains access to that VLAN as a member. NOTE: Nessus has not performed this check. Please review the benchmark to ensure target compliance. Review the device configuration to determine if all disabled ports have been placed into an unused VLAN. The VLAN must not be VLAN 1. If disabled ports are not assigned to an unused VLAN or have been placed into VLAN 1, this is a finding.
Assign all disabled ports to an unused VLAN. Do not use VLAN1.