You already know that if you want to lock down your Wi-Fi network, you should opt for WPA encryption because WEP is easy to crack. But did you know how easy? Take a look.

Today we’re going to run down, step-by-step, how to crack a Wi-Fi network with WEP security turned on. But first, a word: Knowledge is power, but power doesn’t mean you should be a jerk, or do anything illegal. Knowing how to pick a lock doesn’t make you a thief. Consider this post educational, or a proof-of-concept intellectual exercise.

Dozens of tutorials on how to crack WEP are already all over the internet using this method. Seriously—Google it. This ain’t what you’d call “news.” But what is surprising is that someone like me, with minimal networking experience, can get this done with free software and a cheap Wi-Fi adapter. Here’s how it goes.

What You’ll Need

Unless you’re a computer security and networking ninja, chances are you don’t have all the tools on hand to get this job done. Here’s what you’ll need:

• A compatible wireless adapter—This is the biggest requirement. You’ll need a wireless adapter that’s capable of packet injection, and chances are the one in your computer is not. After consulting with my friendly neighborhood security expert, I purchased an Alfa AWUS050NH USB adapter, pictured here, and it set me back about $50 on Amazon. The guy in this video below is using a $12 model he bought on Ebay (and is even selling his router of choice). You won’t go wrong with the Alfa, but do your research. There are plenty of resources on getting aircrack-compatible adapters out there.
• A BackTrack 3 Live CD. We already took you on a full screenshot tour of how to install and use BackTrack 3, the Linux Live CD that lets you do all sorts of security testing and tasks. Download yourself a copy of the CD and burn it, or load it up in VMware to get started. (I tried the BackTrack 4 pre-release, and it didn’t work as well as BT3. Do yourself a favor and stick with BackTrack 3 for now.)
• A nearby WEP-enabled Wi-Fi network. The signal should be strong and ideally people are using it, connecting and disconnecting their devices from it. The more use it gets while you collect the data you need to run your crack, the better your chances of success.
• Patience with the command line. This is an ten-step process that requires typing in long, arcane commands and waiting around for your Wi-Fi card to collect data in order to crack the password. Like the doctor said to the short person, be a little patient.

Crack That WEP

To crack WEP, you’ll need to launch Konsole, BackTrack’s built-in command line. It’s right there on the taskbar in the lower left corner, second button to the right. Now, the commands.

First run the following to get a list of your network interfaces:

airmon-ng

The only one I’ve got there is labeled ra0. Yours may be different; take note of the label and write it down. From here on in, substitute it in everywhere a command includes (interface).

Now, run the following four commands. See the output that I got for them in the screenshot below.


airmon-ng stop (interface)
ifconfig (interface) down
macchanger --mac 00:11:22:33:44:55 (interface)
airmon-ng start (interface)

If you don’t get the same results from these commands as pictured here, most likely your network adapter won’t work with this particular crack. If you do, you’ve successfully “faked” a new MAC address on your network interface, 00:11:22:33:44:55.

Now it’s time to pick your network. Run:

airodump-ng (interface)

To see a list of wireless networks around you. When you see the one you want, hit Ctrl+C to stop the list. Highlight the row pertaining to the network of interest, and take note of two things: its BSSID and its channel (in the column labeled CH), as pictured below. Obviously the network you want to crack should have WEP encryption (in the ENC) column, not WPA or anything else.

Like I said, hit Ctrl+C to stop this listing. (I had to do this once or twice to find the network I was looking for.) Once you’ve got it, highlight the BSSID and copy it to your clipboard for reuse in the upcoming commands.

Now we’re going to watch what’s going on with that network you chose and capture that information to a file. Run:

airodump-ng -c (channel) -w (file name) --bssid (bssid) (interface)

Where (channel) is your network’s channel, and (bssid) is the BSSID you just copied to clipboard. You can use the Shift+Insert key combination to paste it into the command. Enter anything descriptive for (file name). I chose “yoyo,” which is the network’s name I’m cracking.

You’ll get output like what’s in the window in the background pictured below. Leave that one be. Open a new Konsole window in the foreground, and enter this command:

aireplay-ng -1 0 -a (bssid) -h 00:11:22:33:44:55 -e (essid) (interface)

Here the ESSID is the access point’s SSID name, which in my case is yoyo. What you want to get after this command is the reassuring “Association successful” message with that smiley face.

You’re almost there. Now it’s time for:

aireplay-ng -3 -b (bssid) -h 00:11:22:33:44:55 (interface)

Here we’re creating router traffic to capture more throughput faster to speed up our crack. After a few minutes, that front window will start going crazy with read/write packets. (Also, I was unable to surf the web with the yoyo network on a separate computer while this was going on.) Here’s the part where you might have to grab yourself a cup of coffee or take a walk. Basically you want to wait until enough data has been collected to run your crack. Watch the number in the “#Data” column—you want it to go above 10,000. (Pictured below it’s only at 854.)

Depending on the power of your network (mine is inexplicably low at -32 in that screenshot, even though the yoyo AP was in the same room as my adapter), this process could take some time. Wait until that #Data goes over 10k, though—because the crack won’t work if it doesn’t. In fact, you may need more than 10k, though that seems to be a working threshold for many.

Once you’ve collected enough data, it’s the moment of truth. Launch a third Konsole window and run the following to crack that data you’ve collected:

aircrack-ng -b (bssid) (file name-01.cap)

Here the filename should be whatever you entered above for (file name). You can browse to your Home directory to see it; it’s the one with .cap as the extension.

If you didn’t get enough data, aircrack will fail and tell you to try again with more. If it succeeds, it will look like this:

The WEP key appears next to “KEY FOUND.” Drop the colons and enter it to log onto the network.

Problems Along the Way

With this article I set out to prove that cracking WEP is a relatively “easy” process for someone determined and willing to get the hardware and software going. I still think that’s true, but unlike the guy in the video below, I had several difficulties along the way. In fact, you’ll notice that the last screenshot up there doesn’t look like the others—it’s because it’s not mine. Even though the AP which I was cracking was my own and in the same room as my Alfa, the power reading on the signal was always around -30, and so the data collection was very slow, and BackTrack would consistently crash before it was complete. After about half a dozen attempts (and trying BackTrack on both my Mac and PC, as a live CD and a virtual machine), I still haven’t captured enough data for aircrack to decrypt the key.

So while this process is easy in theory, your mileage may vary depending on your hardware, proximity to the AP point, and the way the planets are aligned. Oh yeah, and if you’re on deadline—Murphy’s Law almost guarantees it won’t work if you’re on deadline.

To see the video version of these exact instructions, check out this dude’s YouTube video.

Got any experience with the WEP cracking courtesy of BackTrack? What do you have to say about it? Give it up in the comments.

Gina Trapani, Lifehacker’s founding editor, is tired of typing commands that start with “air.” Her weekly feature, Smarterware, appears every Wednesday on Lifehacker. Subscribe to the Smarterware tag feed to get new installments in your newsreader.

Go to Source

How to Crack a Wi-Fi Network’s WEP Password with BackTrack [Wi-Fi] originally appeared on Shai Perednik.com on July 1, 2009.

Amnesty International has installed a new anti-domestic-abuse ad fixture in Hamburg, Germany which is equal parts clever and shocking: when you look at the photo, it’s a smiling couple; when you look away, it’s a dude punchin’ a lady.

The billboard works by scanning its proximity with an eye-tracking camera, which triggers an image switch on the display panel when it senses someone looking at it. The change only occurs after a brief delay, so that observers understand what’s going on, and get the message.

It’s a fantastically effective concept, and a brilliant use of technology. Kind of sad, then, that it’s probably award bait, and doomed to be a lone installation, according to Copyranter. [Copyranter via Dvice]

Go to Source

Anti-Abuse Bus Stop Ad Only Batters Women When Nobody’s Looking [Advertising] originally appeared on Shai Perednik.com on June 26, 2009.

Would you like to be able to use the magic of Bluetooth to automatically pause iTunes, set your away message in Adium, and lock the screen simply by standing up and walking away from your desk? Of course you would — it’s future-tastic (jetpacks not included)! Let’s take a look at how to pull this off.

What You’ll Need

First you’ll need a copy of Proximity, a handy (and free) little application which monitors your Bluetooth-enabled device and fires off AppleScripts when it leaves and enters connection range. As an added touch, we’ll also use a copy of DeskShade to lock and unlock the computer with style, leaving a nice away message displayed on the screen and opening a “Hacker Log” to display what activity took place while you were away.

DeskShade actually does a lot more than just allow AppleScript to lock and unlock your screen. I won’t go into a full review of it here, but essentially, it will also help keep your desktop clean, your wallpaper fresh, and your mind uncluttered. If, however, you want to forgo the use of DeskShade, you can instead lock and unlock the computer by having AppleScript launch your screensaver and adjust the security settings required for waking it up. AppleScript files for both approaches can be downloaded here (8kb, ZIP).

Getting Set Up

Install Proximity, and from within the preferences pane select your Bluetooth device. I used my iPhone, but any “discoverable” device should work. In the AppleScript section link to OutofRange.scpt for when the device moves out of range and InRange.scpt for when it moves back in range. Make sure that monitoring is enabled and set a frequency for proximity checks — I used 60 seconds. If you decided not to go the DeskShade route, then just swap in the second set of scripts for that step above and skip ahead to the testing.

Install DeskShade and on the DeskLock tab set a password, enable AppleScript to unlock, set the Hacker Log to open after unlocking and set the away message to something appropriate. I used the same “More than 30ft away from my computer” message that is set in Adium via the out-of-range script.

Future Perfect

It’s as simple as that. Get up and take a walk around to test it out; by the time you get back, your computer should be unlocked, and you can have a look at the Hacker Log to see what happened while you were gone. Now all we need are jetpacks, flying cars, and a reliable way to prevent “sock-loss” when doing the laundry, and it will be future perfect.

via theappleblog.com

How-To: Proximity Automation originally appeared on Shai Perednik.com on June 11, 2009.