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What kind of attack is MAC address flooding?
MAC address flooding attack (CAM table flooding attack) is a type of network attack where an attacker connected to a switch port floods the switch interface with very large number of Ethernet frames with different fake source MAC address.
Can a MAC flooding attack be used for VLAN hopping?
MAC flooding can also be used as a rudimentary VLAN hopping attack. To prevent MAC flooding attacks, network operators usually rely on the presence of one or more features in their network equipment:
What can be done to prevent MAC flooding?
Counter measures. To prevent MAC flooding attacks, network operators usually rely on the presence of one or more features in their network equipment: With a feature often called “port security” by vendors, many advanced switches can be configured to limit the number of MAC addresses that can be learned on ports connected to end stations.
How are Cisco switches protected from MAC flooding?
The attacker’s machine will be delivered with all the frames between the victim and another machines. The attacker will be able to capture sensitive data from network. Cisco switches are packed with in-built security feature against MAC flooding attacks, called as Port Security.
MAC address flooding attack is very common security attack. MAC address table in the switch has the MAC addresses available on a given physical port of a switch and the associated VLAN parameters for each. MAC flooding attacks are sometimes called MAC address table overflow attacks.
When does unicast flooding happen in a switch?
Unicast flooding is happening in situation when switch receives frame with unknown destination MAC address (switch has no MAC address present in MAC address table (CAM table) on any port).
How does a MAC address table overflow work?
From now on any frame sent by host A (or any other host) to host B is forwarded to port 2 of the switch and not broadcast out every port. The switch is working like it should. This is the main goal of switch functionality, to have separate collision domain for each port on the switch.
What is an Ethernet frame and what is MAC flooding?
An Ethernet frame is a physical layer communication transmission, comprised of 6 fields which are assembled to transmit any higher layer protocol over an Ethernet Fabric. What is MAC Flooding? The MAC Flooding is an attacking method intended to compromise the security of the network switches.
MAC address flooding attack (CAM table flooding attack) is a type of network attack where an attacker connected to a switch port floods the switch interface with very large number of Ethernet frames with different fake source MAC address. Following images shows a Switch’s MAC address table before and after flooding attack.
Why does the switch flood all ports with incoming traffic?
When the MAC address table is full, the switch floods all ports with incoming traffic because it cannot find the port number for a particular MAC address in the MAC address table. The switch, in essence, acts like a hub. Network attack tools are generating about 160,000 MAC entries on a switch per minute.
How often does a MAC address table overflow?
The switch, in essence, acts like a hub. Network attack tools are generating about 160,000 MAC entries on a switch per minute. Depending on the type of switch, the MAC address table size can be different but is always vulnerable to the flood attack. Sooner or later the table will be filled up.