CISC-L2-000220 - The Cisco switch must not have the default VLAN assigned to any host-facing switch ports.

Information

In a VLAN-based network, switches use the default VLAN (i.e., VLAN 1) for in-band management and to communicate with other networking devices using Spanning-Tree Protocol (STP), Dynamic Trunking Protocol (DTP), VLAN Trunking Protocol (VTP), and Port Aggregation Protocol (PAgP) - all untagged traffic.

As a consequence, the default VLAN may unwisely span the entire network if not appropriately pruned. If its scope is large enough, the risk of compromise can increase significantly.

NOTE: Nessus has not performed this check. Please review the benchmark to ensure target compliance.

Solution

Remove the assignment of the default VLAN from all access switch ports.

See Also

https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_Cisco_IOS_Switch_Y24M07_STIG.zip

Item Details

Category: SYSTEM AND COMMUNICATIONS PROTECTION

References: 800-53|SC-7, CAT|II, CCI|CCI-004891, Rule-ID|SV-220642r991849_rule, STIG-ID|CISC-L2-000220, STIG-Legacy|SV-110255, STIG-Legacy|V-101151, Vuln-ID|V-220642

Plugin: Cisco

Control ID: 823d2253dfae54de0d986574a1840b741bacf10673f91fed8ac64fdf5894824d