NET-VLAN-006 - The VLAN1 is being used for management traffic.

Information

A dedicated management VLAN or VLANs must be configured to keep management traffic separate from user data and control plane traffic.

All ports, including the internal sc0 interface, are configured by default to be members of VLAN 1. In a VLAN-based network, switches use VLAN 1 as the default VLAN for in-band management and to communicate with other networking devices using Spanning-Tree Protocol (STP), Cisco Discovery Protocol (CDP), Dynamic Trunking Protocol (DTP), VLAN Trunking Protocol (VTP), and Port Aggregation Protocol (PAgP) all untagged traffic. As a consequence, VLAN 1 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.

Review the device configurations to determine if a dedicated VLAN(s) have been implemented for the management network. VLAN 1 must not be used. If a dedicated VLAN or VLANs have not been established for the management network, this is a finding. If VLAN 1 is used for management, this is also a finding.

Solution

Best practices for VLAN-based networks is create a dedicated management VLAN, prune unnecessary ports from gaining access to VLAN 1 as well as the management VLAN, and to separate in-band management, device protocol, and data traffic.

See Also

https://iasecontent.disa.mil/stigs/zip/U_Network_L2_Switch_V8R27_STIG.zip

Item Details

References: CAT|II, Rule-ID|SV-5628r2_rule, STIG-ID|NET-VLAN-006, Vuln-ID|V-5628

Plugin: Cisco

Control ID: d4a46c59c13c509c3f260f3e9a5c776b9cb31c1ffdce6bd70045e55b28f289fa