The Cisco switch must not use the default VLAN for management traffic.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-220644	CISC-L2-000240	SV-220644r991852_rule	CCI-004931	medium
Description
Switches use the default VLAN (i.e., VLAN 1) for in-band management and to communicate with directly connected switches 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.
STIG			Date
Cisco IOS Switch L2S Security Technical Implementation Guide			2026-05-01

Related Frameworks

1 mapping across 3 frameworks

SCF0 mappings

No source states a mapping between these directly.

Also reachable in 3 hops (1) derived by us, not asserted by any source

Each of these is a route we composed by chaining published mappings. No publisher states a relationship between the two endpoints.

BCD-10.4Alternate Communications Channels

1.00

DISA STIG Benchmark (XCCDF)V3R2intersects(normalised)
DISA CCI List2025-01-23equal to(normalised)
SCF Secure Traceability Relationship Mapping (STRM)2026.2equal to

NIST 800-530 mappings

No source states a mapping between these directly.

Also reachable in 2 hops (5) derived by us, not asserted by any source

Each of these is a route we composed by chaining published mappings. No publisher states a relationship between the two endpoints.

SC-47Alternate Communications Paths

1.00

DISA STIG Benchmark (XCCDF)V3R2intersects(normalised)
DISA CCI List2025-01-23equal to(normalised)

SC-5(2)Capacity, Bandwidth, and Redundancy

1.00

DISA STIG Benchmark (XCCDF)V3R2intersects(normalised)
DISA STIG Benchmark (XCCDF)V2R1our copyintersects(normalised)
DISA STIG Benchmark (XCCDF)V2R1intersects(normalised)
DISA CCI List2025-01-23equal to(normalised)

SC-7Boundary Protection

1.00

DISA STIG Benchmark (XCCDF)V3R2intersects(normalised)
DISA STIG Benchmark (XCCDF)V2R2our copyintersects(normalised)
DISA STIG Benchmark (XCCDF)V2R2intersects(normalised)
DISA CCI List2025-01-23equal to(normalised)

SC-7(11)Restrict Incoming Communications Traffic

1.00

DISA STIG Benchmark (XCCDF)V3R2intersects(normalised)
DISA STIG Benchmark (XCCDF)V2R1our copyintersects(normalised)
DISA STIG Benchmark (XCCDF)V2R1intersects(normalised)
DISA CCI List2025-01-23equal to(normalised)

SC-7(29)Separate Subnets to Isolate Functions

1.00

DISA STIG Benchmark (XCCDF)V3R2intersects(normalised)
DISA STIG Benchmark (XCCDF)V1R1our copyintersects(normalised)
DISA STIG Benchmark (XCCDF)V1R1intersects(normalised)
DISA CCI List2025-01-23equal to(normalised)

CCI1 mapping

CCI-004931

1.00

DISA STIG Benchmark (XCCDF)V3R2intersects(normalised)

Details

Check Text (C-220644r991852_chk)

Review the switch configuration and verify that the default VLAN is pruned from trunk links that do not require it: SW1#show interfaces trunk Port Mode Encapsulation Status Native vlan Gi0/1 on 802.1q trunking 1 Gi0/2 on 802.1q trunking 1 Port Vlans allowed on trunk Gi0/1 1-998,1000-4094 Gi0/2 1-4094 If the default VLAN is not pruned from trunk links that should not be transporting frames for the VLAN, this is a finding.

Fix Text (F-22348r507979_fix)

Configure the switch for management access to use a VLAN other than the default VLAN: SW1(config)#int vlan 22 SW1(config-if)#ip add 10.1.22.3 255.255.255.0 SW1(config-if)#no shut