Which of the following statements are true about firewalking?
Each correct answer represents a complete solution. Choose all that apply.

A.
Firewalking works on the UDP packets.

B.
A malicious attacker can use firewalking to determine the types of ports/protocols that can
bypass the firewall.

C.
To use firewalking, the attacker needs the IP address of the last known gateway before the
firewall and the IP address of a host located behind the firewall.

D.
In this technique, an attacker sends a crafted packet with a TTL value that is set to expire one
hop past the firewall.

Explanation: