Ophcrack – A Password Hack Tool to Crack Almost Any Windows Password

pw   Ophcrack   A Password Hack Tool to Crack Almost Any Windows PasswordThere are a lot of different reasons why one would want to use any number of password hack tools to hack a Windows password. Of course, there are the good-hearted reasons, like helping your grandpa because he forgot his password and is locked out of his own computer. Then, there are the more dubious reasons, like spying on your accountant.

In the past, MakeUseOf has published other password-cracking related articles. Those who are interest should check out T.J. Miniday’s 3 Ways to Reset Forgotten Windows Administrator Password.

However, there might be circumstances in which you’d need unnoticed access – being able to use the terminal without literally changing the password.

Ophcrack

That’s where Ophcrack comes in. Ophcrack is one of the more effective password hack tools that runs via Windows, Mac and Linux installations or on a Live CD, and it can be used to crack almost any Windows password.

To manage this, Ophcrack uses rainbow tables to guess the password. When a working one is encountered, it is presented to you, and you can simply log in with it. One would think this “guessing” takes a lot of time, but that’s just where the power of rainbow tables lies.

ophcrack2   Ophcrack   A Password Hack Tool to Crack Almost Any Windows Password

Rainbow Tables in a Nutshell

Operation systems don’t store the user passwords in plain text — that’d be highly insecure, and even right out stupid. Instead, they calculate the hashes of the passwords by putting the passwords through a one-way hash function and store those. When one would obtain these hashes, they would still be rather useless; the password needs to be entered, after which the hash needs to be calculated and compared to the stored password hash.

e.g. ‘makeuseof.com’ would become ‘9fb883363640e11970be10a5936a37fc:b35f6f8268073d2242e0cd8b72554d8a’ when converted to Windows XP’s LM hash.

A rainbow table is basically an enormous list of passwords — basically every password a brute force attack would try — with their respective hashes included. Although this table takes a lot of time to generate, it can reduce the cracking of passwords to minutes, or even seconds.

Downloadable Tables

Ophcrack supplies a few of these rainbow tables, free, for your use. They’re included in the Live CD, can automatically be retrieved from the Windows executable, or downloaded from the Ophcrack website. We’ll quickly look over the available tables, and their possibilities.

For Windows XP, Ophcrack supplies two alphanumeric tables. With these, you can crack 99.99% of all passwords under 14 characters, consisting of a combination between letters and numbers — abcdefghijklmnopqrstuvwxyz0123456789. Because the LM hash used by Windows XP is insensitive to capitalization, these hash tables contain 80 billion different hashes, corresponding with 12 septillion possible passwords.

tables xp   Ophcrack   A Password Hack Tool to Crack Almost Any Windows Password

You can choose between the XP free small and the XP free fast tables. These can both be used to crack the same passwords, but because the XP free fast table is twice as large, you can crack them in half the time.

The downside of both tables is their unability to crack passwords with special characters — these can only be cracked using the premium XP special tables.

For Windows Vista, which abandoned the weak LM hash, and moved on to the stronger NT hash, there are less possibilities. Currently, Ophcrack only gives away a table with dictionary-words and variations (hybrids) for free. If you’re willing to cough up a lot of money (about 99$), they also provide alphanumerical tables – including special characters.

tables vista   Ophcrack   A Password Hack Tool to Crack Almost Any Windows Password

Because the NT hash is subjective to capitalization, and allows a much greater password length (whereas the LM hash simply splits large sequences up in multitudes of smaller strings), these premium rainbow tables can range in size from 8GB to over 130GB.

And that’s the essence of it. There’s some more technical information (a real how-to) in the Ophcrack help files (included in the downloads).

If you’re shivering in your boots after reading this article and thinking,”Gosh, everyone’s going to know how to hack my password. What shall I do?” Then it may be a good time to create a stronger password. Stefan wrote about 5 free password generators that will help you make nearly unhackable passwords, no matter what password hack tools a hacker tries to use. It’s a good start.

So, what do you think? Is Ophcrack really the pot of gold at the end of the rainbow, or hardly worth one’s attention? — Let us know your experiences, opinions and questions in the comments section below.

The comments were closed because the article is more than 180 days old.

If you have any questions related to what's mentioned in the article or need help with any computer issue, ask it on MakeUseOf Answers—We and our community will be more than happy to help.

30 Comments -

0 votes

Binoyxj

Sounds interesting.Gonna test this tool now.Thanks for sharing.

0 votes

Merryann Palmer

I really need something like this to get into my old Toshiba with XP. BUT – when I downloaded, AVG informed me the file is infected with a Trojan and killed it.

Is this something it’s supposed to have, or did someone slip it in the installer?

0 votes

Simon Slangen

It isn’t uncommon for a ‘password cracker’ to be labeled bad-ware. To my knowledge, AVG is (one of) the only anti-virus apps waving the red flag with Ophcrack – and still without reason.

0 votes

Simon Slangen

There was a ticket submitted (and resolved) to Sourceforge about this issue. I quote:

* resolution set to fixed

Greetings,

ophcrack is a password retrieval tool. Accordingly, many virus utilities will flag it as potentially harmful, as it is. Used properly and lawfully, there is likely nothing wrong with it.

Thank you,

David Burley
Systems Programmer/Analyst, SourceForge.net

0 votes

Carl

Will this work with the system password? I have a password I cannot remember on my laptop before I get to the XP login.

0 votes
0 votes

Leo

Heh heh, BIOS passwords are a trivial issue if you are the device owner and can take your time. First, there are large lists published to the internet of those master codes you’re refering to, but more importantly…

A BIOS password is stored in volatile memory that is supported by the CMOS battery (Little watchbattery looking thing the size of a washer.) Remove the laptop battery, AC-adapter cord and then pen the laptop and remove the CMOS battery. Attempt to power it on a few times (Hold power button for 45seconds or so, repeat) This is usually enough to drain the residule charge from the capacitors and wipe the volatile memory. If that fails, do it again, and wait 24-48hours before putting any power back to the device.

0 votes

Raul

Well my anti-virus calls this a malware!

0 votes

Sean

Well good for you! Go have a cookie…

Get a new AV engine or report the false-positive. Ophcrack isn’t a virus.

0 votes

Simon Slangen

That’s right. With Ophcrack’s popularity and the complete absence of any reported problems, Occam’s Razor rules out the malware possibility.

Security companies just don’t like rainbow tables/brute force/… in their eyes this might be enough to label it malware.

0 votes

Yodster

I am curious about one thing. Other than cracking a password without showing it has been cracked, how is this better than clearing our th windows passwords with the many live CDs out there?

Clearing out the password tends to take a minute or so and allows you to just login. Is there any sort of data loss that doesn’t occur when the password is cracked?

0 votes

Simon Slangen

No, clearing out the password has the same result. Except, of course, that the password is then gone.

0 votes

Leo

Actually, I’m afraid you are incorrect on that account.
Ther is infact data loss that occurs when you clear or force a change upon a user password. Or rather data loss that *could occur* Your security encryption keys are linked to your name/password combination at the time the password is set using the proper creation tool. If you use a tool that forces a change on the password, it does not update the encrytion keys associated with your account, thus creating a loss of any files using the EFS (Encrypting File System) in windows.

The only way to recover said lost data is if you already had a backup-operator/recovery operator account created with saved copies of the encryption keys exported for later data recovery scenarios. While such is the suggested practice is large corporate scenarios, it’s rarely followed even there, none the less on a home user’s computer.

0 votes

linky1124

it didn’t work sometimes.
then my friend recommend another recovery tool to me.
http://www.resetwindowspassword.com/
and it work.

0 votes

hackercracker

this is 100% legit. i have a live cd for vista and xp. its worth having just in case. just ignore the warnings from antivirus scanners. they dont want you to have a password crack tool, maybe because you can crack any laptop/desktop with this.

0 votes

Aryan

Latest Hacking Tools and Yahoo hacks only on http://dark-coderz.blogspot.com

0 votes

Atomuhr

Used it in Vista, it worked, password was easy though (12345)

0 votes

Andy

If you don’t want to reformat your system, I think you have to make a rest disk or use some tool to do all the job for you. Such as Windows Password Recovery Tool 3.0. Burn a boot CD with the program, and insert it into the problem computer and your password will be reset to “Blank”.

0 votes

suzie

Help!!! Please!!…..Hi all from a computer novice, please be gentle with me lol….I have just downloaded ophcracklive cd for vista, ii burned the cd and then ran it on the computer but somethings not quite right…….I’m ending up with the black screen, loads of stuff on there that i don’t understand but the last message says..”passwords have been saved in /tmp/ophcrack.txt. Does anyone have a clue what i’ve done wrong and how to put it right….pleeeeeeeeeeease, it’s driving me insane lol…Many thanks…Suzie.

0 votes
0 votes

HellKid

someone steal my logout file on da hosting and it’s said da password was encrypted and should be opened using a password encrypter tool, anybody wanna help me out please..?

0 votes

NoEbonics

Sure, I’ll help you. It’s spelled “THE”, not “DA”.

There, that should help you quite a bit in life.

0 votes

Michael Armstrong

I just found a great blog–free windows password recovery methods.
Those all are free and very helpful!

0 votes

Cena

Wow well detailed… but can you also provide some info on recovring lost passwords of windows vista??

0 votes

Fiona

Free trail Windows Password Recovery Tool—Windows Password Unlocker is highly recommended
1.Download Windows Password Unlocker from Password Unlocker Official site
2.Decompress the Windows password unlocker and note that there is an .ISO image file. Burn the image file onto an blank CD with the burner freely supported by Password Unlocker.
3.Insert the newly created CD into the locked computer and re-boot it from the CD drive.
4.After launched the CD, a window pop up with all your account names(if you have several accounts) select one of the accounts that you have forgotten its password to reset it. Just one press, you have removed the password

0 votes

debi

please can anyone help me get my passwords bk to my msn and hotmail account as my ex-partner as changed them

0 votes

Simon Slangen

Try the default password recovery (secret question), or otherwise contact Windows Live support. They’re best equipped to help you with this.

0 votes

Chris

You can reset windows user account password in safe mode(F8 when booting up). But if you forgot administrator password, you must reinstall windows OS or use windows password recovery disk.
http://www.windowsloginrecovery.com

0 votes

Chris

thanx, I have other method to recover windows password now.

0 votes

HellKid

just wanna know if somebody out there could help me out bout my hostin password?