An intrusion-detection system detecting a series of ICMP packets sent to each port from the same IP address might indicate:
A)a Distributed Denial of Service attack in progress
B)scanning of the system for vulnerabilities prior to an attack
C)the system has been infiltrated by an outsider
D)Trojan horse\virus infection sending information back home

Question

Quizplus · Accepted Answer

Scanning of a system for vulnerabilities often involves sending packets to various ports to discover open services or potential weaknesses. A series of ICMP packets sent to each port from the same IP address is indicative of such scanning activity, which attackers typically perform prior to launching an attack.

An Intrusion-Detection System Detecting a Series of ICMP Packets Sent