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Firewalking is a technique that can be used to gather information about a remote network protected by a firewall. This technique can be used effectively to perform information gathering attacks. In this technique, an attacker sends a crafted packet with a TTL value that is set to expire one hop past the firewall. Which of the following are pre-requisites for an attacker to conduct firewalking?
Each correct answer represents a complete solution. Choose all that apply.
Suggested Answer: A, B, D
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25 comments · newest first
ME
Melvin
10 months ago
I thought firewalking was just a myth, but this makes sense.
YE
Yen
10 months ago
Wait, do you really need a backdoor for firewalking? Sounds off.
AM
Ammie
10 months ago
Agree, knowing the last gateway IP is crucial too!
VA
Vashti
10 months ago
ICMP packets must be allowed, that's a must-have!
SH
Shawnda
11 months ago
You definitely need the IP of a host behind the firewall.
KA
Kaycee
11 months ago
I don't think having a backdoor is necessary for firewalking, but I could be wrong. It seems more about the network's configuration.
RE
Rene
11 months ago
The question about the last known gateway sounds familiar; I feel like we practiced something similar in class.
LO
Lorean
11 months ago
I think ICMP packets need to be allowed for firewalking to work, but I can't recall if that's a definite prerequisite.
LA
Lavonna
11 months ago
I remember that knowing the IP address of a host behind the firewall is crucial for firewalking, but I'm not sure if it's the only requirement.
NI
Nidia
12 months ago
This seems pretty straightforward. The key prerequisites are knowing the IP of the last gateway before the firewall, and having ICMP packets allowed out of the network. The other options about a host IP and a backdoor don't seem relevant to the core firewalking technique.
BR
Brent
12 months ago
Okay, I think I see the strategy here. The attacker needs to know the IP of the last gateway before the firewall so they can set the TTL to expire just past that point. That way, they can get info about the firewall and network without needing to know anything about the hosts behind it. The ICMP packets are just a bonus if the network allows them.
NI
Nickolas
12 months ago
Hmm, I'm a bit confused on this one. Do we really need to know the IP of a host behind the firewall? I thought the whole point was to gather info without that knowledge. And what about the ICMP packets - is that a requirement or just a helpful condition?
MA
Malcom
1 year ago
I think I've got this one. The key is knowing the IP address of a host behind the firewall and the IP address of the last gateway before the firewall. That way, you can craft a packet with the right TTL to expire just past the firewall and gather info.
BE
Bernardine
1 year ago
You're right, knowing the IP address of the last known gateway is also a pre-requisite for firewalking.
GE
Georgene
1 year ago
But what about the last known gateway before the firewall? Isn't that important too?
MA
Maia
1 year ago
Yes, that's correct. Knowing the IP address is crucial for firewalking.
BE
Bernardine
1 year ago
I think the attacker needs to know the IP address of a host behind the firewall.
AS
Ashton
1 year ago
Haha, a backdoor? What is this, a spy movie? I doubt that's a prerequisite for firewalking. Maybe the attacker could try knocking on the firewall's door instead.
TE
Teddy
1 year ago
B is also important, right? If ICMP packets are blocked, the attacker won't be able to get the TTL information they need.
LO
Lonna
1 year ago
That's right. If ICMP packets are blocked, the attacker won't be able to gather the necessary TTL information.
CL
Clarence
1 year ago
Yes, you are correct. B is an important prerequisite for an attacker to conduct firewalking.
AR
Aron
1 year ago
Hmm, I think the correct answers are A and D. Knowing the IP address of the host and the last gateway is crucial for this technique to work.
MA
Malika
1 year ago
Having a backdoor installed on the network is not necessary for an attacker to conduct firewalking.
BE
Bernardo
1 year ago
ICMP packets leaving the network being allowed is not a prerequisite for firewalking.
XU
Xuan
1 year ago
Yes, you are correct. Knowing the IP address of the host and the last gateway is essential for firewalking.