Vantaa, Finland June 2007

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For more information:

Mr. Kimmo Rousku

kimmo.rousku@norbu.fi

How to crack Microsoft Windows Vista / XP-workstations and Windows 200x servers in a minute?

Update - 21st June

Some free encryption programs:

There are some freeware encryption software available:

http://www.truecrypt.org/

- Free open-source disk encryption software for Windows Vista/XP/2000 and Linux

http://www.ce-infosys.com/english/downloads/free_compusec/index.html

- so far no Vista-version available

Before you start using any encryption software, make sure you have fresh backups of your computer. Read release notes and installation guides / requirements carefully. I've managed once to encrypt my laptop so that I had to wait 8 days before I was able to try my next password guess, I gave up after about 2 weeks and lost couple of files...

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Update - 17th June

There are many valuable links, which I'd like to recommend for further reading:

KB818200 - An attacker with physical access to a computer may be able to access files and other data http://support.microsoft.com/kb/818200/en-us

- published 31st May 2007 rev 10.

Reduce Your Risk: 10 Security Rules To Live By� http://www.microsoft.com/technet/technetmag/issues/2006/05/ReduceRisk/

May - June 2006 TechNet Magazine / Wes Miller

10 Immutable Laws of Security http://www.microsoft.com/technet/archive/community/columns/security/essays/10imlaws.mspx?mfr=true

10 Immutable Laws of Security Administration http://www.microsoft.com/technet/archive/community/columns/security/essays/10salaws.mspx?mfr=true

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Update 12th June

Making IT easier...



Instead of pressing once "any key" and clicking four mouse clicks to be able to start copying files to usb-disk, you can download Vista WAIK-tools and make a WinPE-boot disk to make the cracking process easier. If you have WinPE boot media, just press "any key" to boot it, wait a couple of minutes and you have full access to your computer - no need for mouse clicks at all.



There are few things I'd like to point out:

- Yes, this is not a new method, I've been using L0phtcrack etc since 90's

- BUT this trick needs no special software nor technical knowledge. Anyone can use this method at any computer, if physical access is available. You don�t have to be able to speak C++ or to� compile kernel.

- Yes, as mentioned later in this page, BIOS-settings can be removed /cracked, the computer's hard disk can be stolen and put to another machine to be copied. Unfortunately there are some (older) bios-versions, which allows user to choose between different boot devices even bios-passwords enabled :-(

- Summary: If you really want to secure your files and systems, I highly recommend you to keep physical access to your computer as tight as possible and ENCRYPT your hard disks.

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11th June

My website http://www.ict-tuki.fi and this document reveal and explain how anyone can crack almost any computer, which uses Microsoft Windows operating system and which doesn�t include any special security components (for example hard disk encryption).

This security feature was found 8th February 2007 during Windows Vista training session and reported immediately to Microsoft Finland Oyj. Further investigations revealed that it is possible to crack other Windows OS versions, too. Also this information was distributed to local Microsoft office. These findings were confirmed 10th February 2007 by Microsoft Finland.

Four months have passed and Microsoft hasn�t given any information nor warned its customers concerning this dangerous feature. Therefore I have decided to inform about this feature via my web pages. So, learn more about this phenomenon and please secure your workstations and servers!

What�s the problem?

This problematic security feature exists because Windows Vista Repair Computer / System Recovery program enables the use of command prompt without any user authentication with highest possible - system-level � priviledges.

Cracking Windows operating systems has been possible by using cracking software found from various web pages. This is the first time when cracking Windows operating systems is really easy and needs no deeper technical knowledge. This is the reason, why everyone using Windows should understand the cracking method and start preparing safety systems, if needed.





1. Requirements:

a) Physical access to workstation / server

b) Windows Vista Installation-DVD-media�

- It�s easy to create a bootable USB flash memory that works in a similar way

- Windows Home Basic, Premium, Business and Ultimate tested

c) For example USB-memory to transfer files

Special note: no user names or passwords are needed

2. Phase 1 � Booting

Start Windows Vista installation from the installation-DVD (you may have to �press any key� in order to boot from DVD, this depends on the BIOS)

- The only realistic solution to keep OS secure, is to make it impossible to boot from any other media than local hard disk.

- Remember to set up BIOS-password. After that it�s not easy to change the booting order.

- As all security experts know, resetting BIOS is possible if there�s free physical access to the computer. If a cracker can open the cover of the computer, he can use the motherboard�s BIOS reset functions to clear all existing passwords.������������������

- Another highly recommended solution to protect the computer is hard disk encryption, which unfortunately isn�t available for most Windows Vista users (only in Enterprise or Ultimate versions). For Windows XP and older systems encrypting is possible only by using 3rd party commercial software.

- Encrypting File System (EFS) could be a solution, too, but it�s not included in Windows Home versions. Many corporate administrators have dropped EFS because of other problems related to folder / file level encryption.

- You can also use a startup password, which can be enabled from BIOS-settings. In corporate environment, managing a large number of startup passwords in a secure way is a very complicated task.

3. Phase 2 � Language / Time & currency / Keyboard selections

Select Vista installation language and press Next





4. Phase 3 � Installation choices

From the main installation menu choose Repair your computer (do not choose Install now).





If installation-DVD / System Recovery doesn�t recognize the local hard disk because of a missing driver, a new driver can be loaded from the usb-disk or cd. In most cases (even in my 2003 server crack test) it�s not needed, thanks to Plug & Play, so choose Next





5. Phase 4 � Command prompt

Choose Command Prompt from the System Recovery Options menu.

Voil�! Here you have full access to this computer, not only as an administrator but also as a system account user.

After this you can insert usb-memory and copy any non-encrypted file from this computer to usb-memory and steal information without leaving any marks to the system or event viewer logs.





Also, you could for example copy SAM-file (contains names and passwords of local users) from c:\windows\system32\config to usb-memory and start cracking computer�s user password at� remote computer.

A cracker can:

1. � copy files from hard disk to USB, floppy or network server

2. � create / modify / delete files and folders

3. � use most of the MS-DOS like commands

4. � use this method in Vista, XP, 200x

6. What does this mean?

Most computers which use Microsoft Windows OS are vulnerable to local penetration, if a cracker has full access to computer�s hard disk and knows how to use Vista Installation-DVD System Recovery functions.

As a security expert, I believe this is a major security risk found in Microsoft OS.

Even before Vista, different methods were available for attacking Windows OS security, t.ex. using programs which could be downloaded from the internet. However, these methods have been either difficult to use or too demanding for normal users.

Vista Installation-DVD enables anyone to crack Windows OS easily in minutes .





7. How is this possible?

It�s possible, that the recovery command prompt has been intentionally included in Windows Vista with system level user rights and without any authentication, for example to ease problem solving etc. But �.

� by default, there should always be some kind of user authentication, so that only authenticated local administrators are entitled to use command prompt.

There is no reasonable explanation why it�s possible to run this command prompt not only in Vista but also in older Windows OS versions .

- Quality assurance error?

- Not enough testing?

8. Could Microsoft patch this problem?

Is it possible to modify the Repair Computer function in order to make it use authentification (in every OS-versions)?�

Is it possible to block the use of Repair Computer function in other Windows OS�es?

There are no instant solutions available, because millions of customers have already purchased Vista.

However, Microsoft could/ should inform about this security risk and give instructions how to protect oneself against it:

� How to setup startup and BIOS passwords and change boot order

� Recommendations for disk encryption

I wish there was an easy to use BitLocker-type disk encryption software free of charge for all existing Windows OS�es including 2000-XP-Vista. Perhaps it�s now understandable, that every version of Windows Server 2008 includes BitLocker Hard Disk Encryption-technology.





9. Proof-of-concept

The following picture demonstrates how to use this feature to crack and examine files in a computer running Windows Vista. You can follow these instructions to other computers running other versions of Windows operating systems.

This P-O-C is done using Windows Vista Business but you can expect similar results with other Windows operating systems.





My computer includes two folders in the root of c:-drive which I�d like to open using Vista Recovery Options. These folders are Data1_nonEFS and Data2_EFS. First folder is not encrypted, the other one is encrypted with EFS.

Both folders have three files named File1.txt, File2.txt and File3.txt. Their content is similar, but they have different access control list-rights.





�This was supposed to be a secret file!� is in each file.

Files in Data2_EFS-folder are encrypted using build in Encrypting Files System (EFS).





File1 has default security ACL-rights, which consist of four users or groups with slightly different permissions. Practically everyone who uses this computer can have access to this file, because Authenticated Users group have Read & Execute-rights.





File2.txt doesn�t include any typical user rights, instead there are rights only for System to access this file. This is not a common permission, but it demonstrates, how you can access even files like this in command prompt without any problems.

As you can see, even local administrator users don�t have access to this file while running Vista.





File3.txt � there�s no permission to this file at all. As you will later notice, this is not a problem while operating in command prompt if you know how to use two new Windows Vista command line commands.





Data2_EFS-folder contains three similarly named files. Their ACL-rights are the same as in Data1_nonEFS-folder.





Start your computer and insert Vista installation disk immediately to the dvd-drive.

In case of this notice, press quickly �any key�.

If you see this text and bar, you�ve been quick enough. Otherwise, let Vista or other operating system start normally, reboot system and try to be a little quicker next time.

In this case I choose Finnish time¤cy format and Finnish keyboard. Choose your own settings and click Next.





Normally you�d click Install now. This time, click Repair your computer to enter System Recovery options.





In some systems, Vista installation media doesn�t include necessary hard disk drivers. In such case, click Load Drivers and supply drivers needed to get access to hard disk. You can try to use older Windows version drivers, if Vista drivers are not available. If you see the operating system you�d like to enter, click Next to continue.





Unless there are no problems with hard disk drivers, you�ll enter the System Recovery Options menu. There are five options you can choose from, but in this case Command Prompt is what we are looking for.





As you can see, you�ll enter a typical cmd-prompt. X:\Sources is your default folder. Actually, you have entered WindowsPE recovery mode. Here you have many ms-dos-like commands available; use Help to see a list of commands available. The most stunning thing is that there is no kind of a user authentification when entering this command prompt! For security reasons, even basic local administrator authentification would be enough as used in older Windows versions� recovery consoles.





�

By using only four commands, you can find out what File1.txt-file contains! As you can remember, this file was intentionally left unchanged so that any authenticated user could have access to it.

Next mission is to open File2.txt. Instead of type-command, I�ll to open it into notepad using start File2.txt command.





Notepad opens and shows File2.txt contents! And the only acl-right in this file was given to System:





What about File3.txt, which has no permissions at all? Fortunately, Windows Vista has a a league of new command line utilities, which are in this case very handy.





Takeown-command makes it possible to take ownership in command line. After you have become the owner of File3.txt, you can set ACL-rights by using a new icacls-command, which replaces the old cacls-command. Now you have full access to File3.txt.





After opening all three files in C:\Data2_nonEFS-folders, let�s have a look at C:\Data2_EFS-folder. Because this folder is encrypted using EFS, there is no simple method in my knowledge to open these encrypted files in the command prompt.





Summary:

To protect you computer or workstation, try to:

- setup bios boot order so that booting from other media than hard disk is not possible

- setup startup password from your bios (mainly in home computers)

- use hard disk encryption software, if possible

- encrypt files and folders using EFS, if mechanisms above are not possible