Thursday 2nd of September 2010

How to crack a Windows XP password

November 18, 2008 by Ivan  
Filed under Articles, Hacks, Password Hacks, Windows Tips

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To crack Windows XP password we’ll use a program I personally used a hundreds of times, called Ophcrack

Well, to crack a password there is one big science discipline called cryptography. Here we won’t get into details but rather explain how this program works.

So, if you lock your account in Windows with a password for example admin, here is what happens. Windows takes that password and encrypts it with one of the methods of encryption and then saves it into a file(with Windows XP it’s a SAM file located in system32). Now your password is no longer stored as admin, but rather something like 3ujf92+*?jdhsa=)jsadn , depending on the encryption method. However, we ask ourselves, why don’t we just take that encrypted password and decrypt it back to admin. The thing is we can’t because it’s a one way encryption and that is actually the point of it all. So how do we actually crack it?

There is a number of methods but the most famous one is brute force attack. Brute force actually means to start with a letter a and encrypting it. Then see if the encrypted strings match. If not then b, c, … until we’ve gotten to admin. Then the encrypted strings will match and we’ll know that is the right password. Brute force attack is the slowest method of cracking, but there is no risk that you’ll not find the password. The thing about brute force is that the time of cracking rises rapidly depending on how long the password is, how many characters are being used in it and so forth.

Other methods, such as dictionary attack and an attack using rainbow tables are a better option. Ophcrack itself works using rainbow tables and brute force combined.

1. Download Ophcrack LiveCD

2. This program is now an ISO image. Just burn it with Nero or whatever you’re already using for burning images( for burning only ISO images download this burning program – ISORecorder)

3. Now reboot your computer with the CD inside (if the CD will not boot you need to set the boot priority inside BIOS, so that the CD-ROM is the first in the list)

4. A menu like this will appear:

crack pasword

Select the Ophcrack Graphic Mode

5. After the CD is done loading, a user interface like this will appear:

crack pasword

The last right column are the passwords for the given users.

Now depending on many reasons, the cracking of the password could take a long time. So the thing I mostly do is go to sleep and by the time I get up in the morning, Ophcrack has cracked it.

Now just reboot your computer and log into Windows. :)



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Comments

10 Comments on "How to crack a Windows XP password"

  1. rajaash on Tue, 3rd Mar 2009 1:26 pm 

    thanks for your information

  2. webmaster tools on Sun, 22nd Mar 2009 5:23 am 

    Well that reminds of a brute force software which I use to decrypt winzip protected file. The methods which you mention here is very much similar and it’s only workable provided that the person setting the password limit him/herself to only certain length or different variables or else it will take ages just to come up with the right combination.

  3. Josh wheeler on Sat, 18th Apr 2009 6:45 am 

    OMG! Im so glad I have found this site! I havent actualy tried anyhting yet but i plan to as soon as possible. My dad changed my password on my computer and i plan on figuring it out because if i reset it, then he will know and get angry adn posibly take away my computer privilages. I am so thankful for people like you who know this info about computers to helpt eh world and the best part is, most people dont even know about this stuff. I’m gonna secretely study hacks becasue i like computers alot. Not enough for a job(but im only 13 so i may change my mind)though. Im not like a real nerd or anyhintg. Im actually considered kinda slow by just about everyone who knows me personally. I really like the post someone had about how you can change the sofware on a download to last forever. I thought that was really neat and that would be funny to have a 90 day trial last 5 years. Anyway, will a 500 mb flashdrive work. I think its 500 mg but im not sure. Its somehting with 500. It’s also about the size of a small butter finger.

  4. Ravikanth on Sat, 9th May 2009 12:25 pm 

    Excellent!!!!!!!!1.

    It’s worked for me you are a life safer.

  5. agus widyatama on Fri, 15th May 2009 10:50 am 

    beatifull solutions, i’ts very worked

  6. kevin on Fri, 20th Nov 2009 7:41 am 

    I have downloaded windows password key 8.0. It is a very quick and useful utility for resetting passwords. It not only supports XP, 2000, and NT, I have personally tested it with Vista Home Premium and Ultimate. It works perfectly to reset any local user account to a blank password.
    Just an easy to use bootable CD/DVD . It can also be used on a USB Flash Drive. http://www.lostwindowspassword.com/

  7. Zach on Mon, 15th Mar 2010 3:36 am 

    I think the best method to recover windows password is using windows password recovery software. Burn the .iso file to a blank CD or a USB flash drive or a floppy disk, insert the CD(USB/floppy disk) into the problem computer and your password will be reset to “Blank” without losing any data and you needn’t reinstall windows OS.

  8. TJS on Tue, 20th Apr 2010 5:14 pm 

    hey i was wondering do you have any methods on cracking bios passwords. i kno there more affectiv but idk how to crack em. im kinda a noob but hey you gota start some where. if any1 has any info on cracking bios passwords then let me know :) all help would be appreciated :). oh i’ve heard of flashing the bios but idk how to do this.

  9. Monica on Sun, 9th May 2010 7:22 pm 

    I love your website and all of its informative links; even the ads are good – however, there is one “stupid” link that tries to load every freaking time that runs a script on your last *.png file, regardless of what it may be. Would you please stop it? I don’t know if you’re trying to load something on my computer or not but it’s the only thing preventing me from telling my friends to access your super site as I know they’ll also mention the png script as well. A message pops up from Windows about the delay it causes and it does allow you to stop it which is good but it’s just annoying as hell which is a shame for such a mondo good site. Just thought I’d let you know about perhaps an ad you’re running that’s doing something you’re not aware of. Best. Monica.

  10. Dragon on Tue, 15th Jun 2010 7:33 am 

    You guys can also try to google- konboot is an iso Image software but, you don’t need to wait for the password.. This would let you go in to windows with no need to enter the admin password then you can go to control panel- user account- and remove or change password then reboot and done

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