What is a VLAN hopping attack?

Virtual local area network hopping (VLAN hopping) is a method of attacking the network resources of the VLAN by sending packets to a port not usually accessible from an end system. The main goal of this form of attack is to gain access to other VLANs on the same network.

What number should you not give to the management VLAN?

Normally the Management VLAN is VLAN 1, but you can use any VLAN as a management VLAN. Cisco recommends not to use VLAN 1 and not to use any VLAN that carries user data traffic as Management VLAN.

What are the best practices for VLAN?

By default, the native VLAN is set to VLAN 1. A recommended best practice is to change the Native VLAN to another unused VLAN where no hosts or other devices reside….Native VLAN

  • The default VLAN will always be VLAN 1.
  • In the same way, the default Native VLAN value will always be VLAN 1, as determined by Cisco.

How do you do VLAN hopping?

Mitigation

  1. Simply do not put any hosts on VLAN 1 (The default VLAN). i.e., assign an access VLAN other than VLAN 1 to every access port Switch (config-if)# switchport access vlan 2.
  2. Change the native VLAN on all trunk ports to an unused VLAN ID.
  3. Explicit tagging of the native VLAN on all trunk ports.

How can VLAN hopping be prevented?

To prevent the VLAN hopping from being exploited, we can do the below mitigations: Ensure that ports are not set to negotiate trunks automatically by disabling DTP: NEVER use VLAN 1 at all. Disable unused ports and put them in an unused VLAN ▪ Always use a dedicated VLAN ID for all trunk ports.

What are the three techniques for mitigating VLAN attacks?

Mitigating a VLAN attack can be done by disabling Dynamic Trunking Protocol (DTP), manually setting ports to trunking mode, and by setting the native VLAN of trunk links to VLANs not in use.

What are some common VLAN security mistakes?

Ten top threats to VLAN security

  • CAM Table Overflow/Media Access Control (MAC) Attack.
  • Address Resolution Protocol (ARP) attack.
  • Switch Spoofing/Basic VLAN Hopping Attack.
  • Double Tagging/Double Encapsulation VLAN Hopping Attack.
  • VLAN Management Policy Server (VMPS)/ VLAN Query Protocol (VQP) attack.

Is VLAN hopping possible?

Any packets sent between VLANs must go through a router or other layer 3 devices. Security is one of the many reasons network administrators configure VLANs. However, with an exploit known as ‘VLAN Hopping’, an attacker is able to bypass these security implementations.

Which actions can you take to prevent VLAN hopping choose two?

Change the native VLAN number to one that is distinct from all user VLANs and is not VLAN 1. Change the management VLAN to a distinct VLAN that is not accessible by regular users. Statically configure all ports that connect to end-user host devices to be in trunk mode. Disable DTP autonegotiation on end-user ports.