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I have my own wifi network at home & recently when I checked the active clients on the wifi I found out the there is one active client. Router shows the MAC address of this client and I want to Access this computer in order to let him know that he's doing a wrong thing. I dont intent to do any harm to his data. I just want to know a method to send him a message saying "Buy you own wifi".

How can I achieve this using a windows 8 computer. Is there any specific softwares that I can use or will the netsend command do the trick!

Thank you.

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Just change your WiFi key. – David Schwartz Feb 23 '13 at 5:38
Sorry, but I think you want to hack into someone's PC for "not-so-good" reasons. If you saw that router shows MAC, then you probably know how to change your router's key ;) If you (probably) don't know what is MAC, then that tools will be dangerous in your hands =) – Jet Sep 11 '13 at 20:19
Clearly this is the simplest solution – RJFalconer Jul 2 '14 at 10:42
up vote 3 down vote accepted

Doing this is non trivial (read "hard" if you don't know your way around networks).

The easiest way is to probably resolve the MAC address into an IP address (Using DHCP to statically assign dynamic IP's is one way of doing this longer term, if its a one off, looking at your routers ARP table or equivalent web page could do you).

You then need to intercept the request and push your own data back. The typical way this would be done would be to use some kind of tproxy and iptables rules along with a custom website.

This is the kind of thing which really needs to be done in the router.

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In your case to "convert" MAC address into IP I'd use a tool like Advanced IP Scanner. And see which IP has that MAC. Also it will show shared folders of that computer (if they exist). And if there are accessible shared folders,... turn on your creativity ;) – Jet Sep 11 '13 at 20:03

If you want to send him the message only then there's a way.. But its very childish type... Whenever he is active on your network then just change the name of your hotspot name.. like "BUY YOU OWN WI-FI" and then lock the mac addresss....

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or the original wifiname_buy.. – barlop Jul 24 '15 at 8:29

"I dont intent to do any harm to his data. I just want to know a method to send him a message saying "Buy you own wifi".

Do you think that you could be overestimating the capabilities of your computer system?

Talking about basics, you can only send the message to a machine with a successful receipt acknowledgment only if that computer is expecting to hear something from your machine?

Moreover, why don't you just close your wifi using a WPA2 password protection instead of changing the world?

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hmmmm nice point on WPA2 password and going with the world! but I would like to try new things! so for that I can't go with the world and I should try to change the world! :) sorry no offense. – Dimal Chandrasiri Feb 23 '13 at 6:47
Cool. I would still consider this be to no-go. – p0lAris Feb 23 '13 at 7:38

If you can access your router and check who's connecting and taking advantage of your internet connection, go to the settings tab of your router and find MAC address filtering or IP address filtering and put that person's data there and block it.

It should be simpler, or you could just change your password mixing small case and big case letters with symbols and numbers, so if somebody would try to hack it, they would lose the will to do so if they see a million years decoding time of their hacking software.

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You might not be it might not be easy with that OS but i will share with you the process.

Before you start your 'attack', you need to do some information gathering. Some of the information requires a tiny bit of math, and programming. Trivial stuff.

His MAC address is composed of 6 Bytes in hexadecimal format. You need to convert this from hex to a floating point, this can be done with the following equation: REDACTED

Once you have converted the MAC address, you need to subtract the number from the last octet of the IP address to get your memory offset. i.e: If the floating point is 122 and the IP address is, the resulting number would be 200-122=78

Once you have your memory offset, you will need to determine the terminal velocity of his modem. This can be done using a cryptographic injection of the isolation buffer. The steps to do this will differ depending on your operating system.

If you are running Windows XP or below, in a command prompt run the following:

inject.library.dll --windows /unix On Windows 7 or Windows 7, the following can be used in Power Shell:

velocity.inject:::DLL internet (buffer overflow) On Linux, the command is as follows:

for i > u ( inject.buffer command IP ) These commands should inject the modem buffer with the proper commands, and output the terminal velocity the modem is running at.

At this point, you will need to download a hacking tool such as ping, telnet, or ftp. You might need to try each tool because it depends on the operating system that his network is running. Generally, linksys network running cat5 are vulnerable to a ping attack, and netgear networks running cat6 are vulnerable to ftp attacks. Apple networks running wifi are vulnerable to telnet attacks.

Once you run your tools, you will be prompted to enter the memory offset to establish a connection. After you establish the connection, you will not have administrator access yet. You will need to send the terminal velocity that you identified earlier, and attach it to a neutral bogon assembly. This step can be tricky, but it's often times easier to just type the velocity in notepad and paste it over and over into the victims modem.

If the velocity attack is successful, you will know. Your desktop and icons might change, and this is an indication that you are in their computer. DON'T WORRY. They can't see what you are doing (this is the point of the memory buffer, remember). They see their windows, and you see yours. Once you are connected, you can browse their Facebook, play music through their speakers, and even start a fire by sending a bunch of sequential writes to their CPU.

Please note: This is provided that you are working in a test environment, or you are official sanctioned by the person or company to perform this penetration test. The rules and laws of your country apply, and I cannot be held responsible for the use of these hacking methods.

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