Câu 20: GCIA: GIAC Certified Intrusion Analyst

Adam works as a Security Administrator for Umbrella Inc. A project has been assigned to him to secure access to the network of the company from all possible entry points. He segmented the network into several subnets and installed firewalls all over the network. He has placed very stringent rules on all the firewalls, blocking everything in and out except ports that must be used. He does need to have port 80 open since his company hosts a website that must be accessed from the Internet. Adam is still worried about programs like Hping2 that can get into a network through covert channels. Which of the following is the most effective way to protect the network of the company from an attacker using Hping2 to scan his internal network?

1. A. Block ICMP type 13 messages — đáp án hiện tại
2. B. Block all outgoing traffic on port 21
3. C. Block all outgoing traffic on port 53
4. D. Block ICMP type 3 messages