Harold is the senior security analyst for a small state agency in New York. He has no other security professionals that work under him, so he has to do all the security-related tasks for the agency. Coming from a computer hardware background, Harold does not have a lot of experience with security methodologies and technologies, but he was the only one who applied for the position.

Harold is currently trying to run a Sniffer on the agency’s network to get an idea of what kind of traffic is being passed around but the program he is using does not seem to be capturing anything. He pours through the sniffer’s manual but can’t find anything that directly relates to his problem. Harold decides to ask the network administrator if the has any thoughts on the problem. Harold is told that the sniffer was not working because the agency’s network is a switched network, which can’t be sniffed by some programs without some tweaking.

What technique could Harold use to sniff agency’s switched network?

A.
ARP spoof the default gateway

B.
Conduct MiTM against the switch

C.
Launch smurf attack against the switch

D.
Flood switch with ICMP packets

Explanation:
ARP spoofing, also known as ARP poisoning, is a technique used to attack an Ethernet network which may allow an attacker to sniff data frames on a local area network (LAN) or stop the traffic altogether (known as a denial of service attack). The principle of ARP spoofing is to send fake, or ‘spoofed’, ARP messages to an Ethernet LAN. These frames contain false MAC addresses, confusing network devices, such as network switches. As a result frames intended for one machine can be mistakenly sent to another (allowing the packets to be sniffed) or an unreachable host (a denial of service attack).