The Ethical Hacker Network - Locked Computer - Limited Account "No Admin Password"

thecount

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Locked Computer - Limited Account "No Admin Password"

« on: July 31, 2008, 04:42:23 AM »

Friends,

I hope you're well.

I'm facing a bit of a dilemma that I would apprecaite some expert assistance with.

I recently got a second hand computer that is completely locked out. At least for a novice/intermediate user like myself.

The only access i have is through a limited user account that has zero privileges as it seems. I can't change anything on the computer. Not even access the calendar. No installation privilieges, no access to bios (password protected), the system boot sequence is set to hard drive only and I can't change it.

I have serached the net and came accross some weak and illogical tricks...none worked for me, not even the password retrival softwares since I can't install them nor booth them. I tried to reset the bios password by removing the backup battery that didn't work either. I wasn't provided with a password reset CD either.

How can I increase the privilieges of this user or reset any of the passwords? I'm Stuck!!!

Thanks in advance.


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apollo

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Re: Locked Computer - Limited Account "No Admin Password"

« Reply #1 on: July 31, 2008, 08:10:19 AM »

This seems to be a good reference on clearing the BIOS password. http://www.dewassoc.com/support/bios/bios_password.htm . My guess is that you may not have left the battery out long enough. Once you do this, there are a few things you can try, including Trinity Rescue CD: http://trinityhome.org/Home/index.php?wpid=1&front_id=12 which a a program called winpass which will let you reset the administrator password.


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don

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Re: Locked Computer - Limited Account "No Admin Password"

« Reply #2 on: July 31, 2008, 09:40:53 AM »

If it's an older system, there is a good chance that there is a jumper on the motherboard that tells BIOS to enable the power on password. Find this jumper, remove it, restart the computer and try getting into BIOS now.

You could always look at the model number of the motherboard and search out the manufacturer and/or manuals. Google is your friend here.

Hope this helps,
Don


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Simon

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Re: Locked Computer - Limited Account "No Admin Password"

« Reply #3 on: August 19, 2008, 08:16:15 PM »

A few things to try:

1. F12 during boot to select an alternate boot device

2. Pull the hard drive and plug it into another system via USB (or otherwise)

3. Log into the system with your existing account and see if the repair directoy has been protected.

One way or another, what you're after is access to the system's drive while booted into an alternate OS. Get the SAM and the SYSTEM files (ideally, from C:\WINDOWS\System32\config if you're booted into an alternate OS, though C:\WINDOWS\repair will work in a pinch). Save them.

Get 0phcrack. Use it to decrypt the SAM (it's SYSKEY encrypted). Just open the SAM file with 0phcrack (it needs to be in the same directory as the SYSTEM file) and then save the results out....don't bother cracking with 0phcrack -- we'll get to that.

Get rainbowcrack. This part is easy (quick d/l).

Get the LANMAN rainbow tables. The full set. Save them somewhere VERY safe, since it's about a 60GB download via bitorrent and will take you the better part of a week.

Run rainbowcrack with the full LANMAN rainbow tables against the decrypted SAM that you grabbed. This will give you every username and password on the system, including the Administrator account.

Sounds like a lot of work....and it is for the first run-through. Once you've done it and have all of the tools that you need (the LANMAN rainbow tables are a bear), it's pretty quick and easy.


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dalepearson

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Re: Locked Computer - Limited Account "No Admin Password"

« Reply #4 on: August 20, 2008, 02:43:28 AM »

Just for clarification, am I reading this right?

You need to access the bios but cant as its password protected?

You can not do alot with the installed OS as you only have a limited access account? What is the OS?


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GaryPod

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Re: Locked Computer - Limited Account "No Admin Password"

« Reply #5 on: October 12, 2008, 08:55:34 AM »

Put the HD in a different PC that you have BIOS access to, run rainbow tables against the windows password via ophtcrack maybe, then place the HD back in the original PC... then you won't need to access the BIOS on the original PC...


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NetStrikr

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Re: Locked Computer - Limited Account "No Admin Password"

« Reply #6 on: October 14, 2008, 02:25:24 AM »

Why not use a live cd and just reset the password?


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shednik

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Re: Locked Computer - Limited Account "No Admin Password"

« Reply #7 on: October 14, 2008, 08:23:45 AM »

Quote from: Simon on August 19, 2008, 08:16:15 PM

This would be the best way to do it IMO...you may not need the rainbow tables but it wouldn't hurt...I've used 0phcrack with the standard tables it came with and it will usually crack the passwords unless there was a special character but then it would only get pieces of it. So its up to you how much you want to download to get this working.


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