Original subtitles

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Information gathering is one of the most important steps

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when it comes to hacking or penetration testing.

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If you think of it, you can't really gain access to a system

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if you don't have enough information about it.

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So, for example, let's say you're connected to a network

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and one of the devices connected to this network

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is your target.

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Now for you to hack into that target,

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first you need to discover all of the connected clients

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to this network, get their MAC address, their IP address,

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and then from there try to maybe gather more information

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or run some attacks in order to gain access to your target.

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Now, there are a number of programs

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that will do this for you.

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Examples are NetDiscover and Nmap,

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which do this job really, really well.

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So in this lecture, we'll start with the simpler one,

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which is NetDiscover and see how to use it to quickly map

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the network we're connected to.

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And in the next lecture,

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I'm gonna show you how to use Nmap

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to gather detailed information about all

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of the clients connected to the same network.

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So, I have my Kali terminal in here, and if I do ifconfig,

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you'll see I have eth0, it has an IP address.

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And like I said, this is the virtual interface created

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by VirtualBox when we set the Kali machine

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to use a NAT network.

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Now, I also said that this NAT network behaves exactly like

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an Ethernet network.

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And as far as the Kali machine is concerned,

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it thinks that it is connected to a real wired network.

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And as you can see in here,

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it's telling me that wired connected.

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Now, I have my virtual Windows machine right here.

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It is configured to use the same NAT network

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as the Kali machine.

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Remember, we're still in the network hacking section,

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so both you and the target machine need to be connected

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to the same network.

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So as far as these two computers are concerned,

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they think that they are connected to the same network.

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So what I wanna do right now is use NetDiscover

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and see how we can use it to discover all devices connected

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to the same network.

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Now the method that I'm gonna show you

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will work exactly the same,

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whether you're using it against a virtual network,

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like I'm doing right now, or against real network,

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and even if your target is a Wi-Fi or a wireless network.

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So all you have to do is type the name of the program,

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which is NetDiscover, and then type dash r

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to specify an IP range to search for.

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This needs to be arranged that can be accessed by you.

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So right now you can see that my IP is 10.0.2.16

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and I can only access IPs on the same subnet.

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So IPs on the same subnet start at 10.0.2.0,

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and they would end at 10.0.2.254

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because 254 is the last IP that a client can have.

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So, my range is gonna be 10.0.2.1

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and I wanna search for clients that might have an IP

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of 10.0.2.1, 10.0.2.2, 10.0.2.3,

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all the way up to 10.0.2.254.

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So instead of manually typing all of these IPs,

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I can just type over 24

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and NetDiscover will automatically know

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that I'm trying to search for all of the IPs

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that start at 10.0.2.1 and end at 10.0.2.254.

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So this is a way of specifying an IP range

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for the whole subnet.

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So if I hit enter now, you'll see that NetDiscover

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will show me all the IPs of the devices connected

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to the same network.

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And note that the first three parts of the IPs

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are always the same because they are on the same subnet.

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And I also have the Mac addresses of these clients

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and Net discovers also attempting

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to guess the device vendor.

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Now, if I press queue, this will quit the program.

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And right now, we have a list of all the connected clients

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to the same network.

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Now, like I said, you can also use this method

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to discover clients connected to the same Wi-Fi network.

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The only thing is, right now, if I do ifconfig,

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you can see that my Kali machine

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does not have a wireless adapter,

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it's not connected to a Wi-Fi network.

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And like I said before,

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you cannot access the built in wireless card

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from a virtual machine.

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Therefore, if you want to do this

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or run any of the wireless attacks that we're gonna see

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in the future against a real computer

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and a real wireless network,

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you're gonna need to use a wireless adapter.

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Now, I'm gonna include links in the description

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that will help you pick a good adapter

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that works with Kali Linux.

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But right now I actually have one,

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and I'm just gonna connect it

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and use it just to prove to you,

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if things work on the virtual machines connected

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to the virtual network,

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they will work exactly the same against a real network

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with real machines.

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So, I'm gonna connect my adapter now.

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And if I do ifconfig, it's still not showing up,

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so I'm gonna connect it from my devices, USB,

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and click on the adapter name,

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and let's see if it shows up now.

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Perfect, as you can see, I have an adapter now called Lan0.

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And what I'm gonna do is,

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I need to connect this adapter to a Wi-Fi network first

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before I can discover all the connected clients

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to this network.

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So I'm gonna go to my network manager,

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I'm gonna click in here

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and you wanna click on Select Network.

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And as you can see, automatically now,

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it's actually connected to a network.

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But in your case, you'd wanna select a network

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and click on Connect,

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and then it will ask you for the password.

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So now I'm actually connected

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and you'll see if I do ifconfig again.

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Right now, lan0 has an IP address.

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So this means that it is connected to a network

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and this means that we can use it now with NetDiscover.

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So again, I'm gonna use the exact same command

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that I used before just to show you and prove to you

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that if this works against virtual machines,

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it will work against real machines.

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And the only difference is going to be the IP.

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So I'm gonna remove this IP.

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And as you can see right now, my IP is 192.168.1.8.

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So therefore, the range that I'm gonna look

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for is gonna start at 192.168.1.1,

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and I'm gonna leave the over 24 here

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because this will tell NetDiscover that I want to start

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at 192.168.1.1 and finish at 192.168.254.

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So if I hit enter now.

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Now, this did not work and I know why.

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In order for this to work,

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you actually have to disable the NAT network.

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So to disable the NAT network, we're gonna go on devices,

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we're gonna go on network,

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and we're gonna uncheck the Connect Network Adapter.

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So now once done with this,

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if we just run the exact same command again.

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As you can see, it's discovering all the connected clients,

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all their IP addresses, all their MAC addresses,

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and it's guessing the manufacturer,

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and you can see it's also discovering

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some Apple devices here.

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So as you can see,

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it's working perfectly using the exact same command.

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Now, I only did this just to show you

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that if things work against virtual machines

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and I guess virtual networks,

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then they will work against real machines

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because these virtual machines and virtual networks

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are modeled of a real machines.

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And as far as the machines are concerned,

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they actually think they are real computers

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and real machines.