Macof is a member of the Dsniff suit toolset and mainly used to flood the switch on a local network with MAC addresses. The reason for this is that the switch regulates the flow of data between its ports. It actively monitors (cache) the MAC address on each port, which helps it pass data only to its intended target. This is the main difference between a switch and a passive hub. A passive hub has no mapping, and thus broadcasts line data to every port on the device. The data is typically rejected by all network cards, except the one it was intended for. However, in a hubbed network, sniffing data is very easy to accomplish by placing a network card into promiscuous mode. This allows that device to simply collect all the data passing through a hubbed network. While this is nice for a hacker, most networks use switches, which inherently restrict this activity. Macof can flood a switch with random MAC addresses. This is called MAC flooding. This fills in the switch’s CAM table, thus new MAC addresses can not be saved, and the switch starts to send all packets to all ports, so it starts to act as a hub, and thus we can monitor all traffic passing through it.
Syntax: macof [-i interface] [-s src] [-d dst] [-e tha] [-x sport] [-y dport] [-n times]
-i interface Specify the interface to send on. -s src Specify source IP address. -d dst Specify destination IP address. -e Specify target hardware address. -x sport Specify TCP source port. -y dport Specify TCP destination port. -n times Specify the number of packets to send.
Macof can flood a switch with random MAC addresses. This is called MAC flooding. This fills in the switch’s CAM table, thus new MAC addresses can not be saved, and the switch starts to send all packets to all ports, so it starts to act as a hub, and thus we can monitor all traffic passing through it.
command: macof -i eth1 -n 10
Macof can flood a switch with random MAC addresses destinated to 192.168.1.1.
command: macof -i eth1 -d 192.168.1.1
While conducting a pentest, this tool comes in handy while sniffing. Some switches don’t allow to spoof arp packets. This tool can be used in such situations to check if the switch is overloaded. Some switches behave like hubs, transmitting all source packets to all destinations. Then sniffing would be very easy. Some switches tend to crash & reboot also. Such kind of layer 2 stress testing can be done with this handy tool.
Some of the major countermeasures against MAC Flooding are:
Learning Without Walls Remote education has long been a lifeline for students in rural areas…
Have you ever come across a picture on the internet and wondered where it came…
Overview WhatsMyName is a free, community-driven OSINT tool designed to identify where a username exists…
Managing disk usage is a crucial task for Linux users and administrators alike. Understanding which…
Efficient disk space management is vital in Linux, especially for system administrators who manage servers…
Knowing how to check directory sizes in Linux is essential for managing disk space and…