Difference between revisions of "TrueCrypt"

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(Keyfiles, plausible deniability.)
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'''TrueCrypt''' is an open source program to create and mount virtual encrypted disks in [[Windows|Windows Vista/XP/2000]] and Linux. It provides two levels of plausible deniability (hidden values / no signatures to make a distinction from random data), on the fly encryption and supports various encryption algorithms (AES-256, Serpent and Twofish).
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{{Infobox_Software |
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  name = Truecrypt |
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  maintainer = TrueCrypt Foundation |
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  os = {{Linux}}, {{Windows}}, OS X |
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  genre = {{Encryption}} |
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  license = TrueCrypt Collective License |
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  website = [http://www.truecrypt.org/ truecrypt.org] |
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}}
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'''TrueCrypt''' is an open source program to create and mount virtual encrypted disks in [[Windows|Windows Vista/XP/2000]] and [[Linux]] and [[Mac OS X|OS X]] as well as [[Whole Disk Encryption]] on Windows. It provides two levels of plausible deniability (hidden values / no signatures to make a distinction from random data), on the fly encryption and supports [[AES]], [[Serpent]] and [[Twofish]].  As of version 6.0 TrueCrypt now supports hidden Operating Systems under Windows only.
  
 
== Forensic Acquisition ==
 
== Forensic Acquisition ==
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If you encounter a system that has a mounted TrueCrypt drive, it is imperative that you capture the contents of the encrypted drive before shutting down the system. Once the system is shutdown, the contents will be inaccessible unless you have the proper encryption key generated by a user's password. You may also need an additional datafile.
 
If you encounter a system that has a mounted TrueCrypt drive, it is imperative that you capture the contents of the encrypted drive before shutting down the system. Once the system is shutdown, the contents will be inaccessible unless you have the proper encryption key generated by a user's password. You may also need an additional datafile.
  
==Attacks==
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== Attacks ==
The only option for acquiring the content of a TrueCrypt drive is to do a brute-force password guessing attack. [[AccessData|AccessData's]] [[Password Recovery Toolkit]] and Distributed Network Attack ([[DNA]]) can both perform such an attack, but DNA is faster.
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The only option for acquiring the content of a dismounted TrueCrypt drive is to do a brute-force password guessing attack. [[AccessData|AccessData's]] [[Password Recovery Toolkit]] and Distributed Network Attack ([[DNA]]) can both perform such an attack, but DNA is faster. Another solution is [[unprotect.info]] that can brute-force password to the file-based encrypted volumes.
  
 
TrueCrypt also supports keyfiles (it uses the first 1024 kilobytes of any file, but can also use it's PRNG to generate such keys). It is important to look for anything that might be used as a keyfile (such as a 1024k file on a USB stick).
 
TrueCrypt also supports keyfiles (it uses the first 1024 kilobytes of any file, but can also use it's PRNG to generate such keys). It is important to look for anything that might be used as a keyfile (such as a 1024k file on a USB stick).
  
The existence of a FAT volume may be an indication of the existence of hidden volumes (a hidden volume can only be created within a FAT TrueCrypt volume).
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== Hidden volumes ==
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Hidden volume is a volume hidden within the free space of another TrueCrypt volume. Even when the outer volume is mounted, it is hard to prove whether there is a hidden volume or not.
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When a hidden volume is mounted, the operating system and third-party applications may write to non-hidden volumes information about the data stored in the hidden volume (e.g. filenames). It is important to look for such kind of information.
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Previous versions of encrypted containers may be found in the journaling filesystems. It is important to track any changes within the free space of the outer container to detect presence of a hidden container.
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== Hidden Operating Systems ==
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Hidden operating system is a system that is installed in a hidden TrueCrypt volume.
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It is possible to detect network-enabled hidden operating systems by matching downloaded content (from a network dump) with data on a possible decoy system.
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Investigator can also detect boot times by searching network dumps for IP packets with low IDs (only if [[Windows]] system is permanently connected to a LAN) and [[TCP timestamps]].
  
 
== External Links ==
 
== External Links ==
  
 
* [http://www.truecrypt.org/ Official website]
 
* [http://www.truecrypt.org/ Official website]
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* [http://www.truecrypt.org/docs/?s=version-history Version history]
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[[Category:Encryption]]
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[[Category:Disk encryption]]

Revision as of 14:05, 13 May 2011

Truecrypt
Maintainer: TrueCrypt Foundation
OS: Linux,Windows, OS X
Genre: Encryption
License: TrueCrypt Collective License
Website: truecrypt.org

TrueCrypt is an open source program to create and mount virtual encrypted disks in Windows Vista/XP/2000 and Linux and OS X as well as Whole Disk Encryption on Windows. It provides two levels of plausible deniability (hidden values / no signatures to make a distinction from random data), on the fly encryption and supports AES, Serpent and Twofish. As of version 6.0 TrueCrypt now supports hidden Operating Systems under Windows only.

Forensic Acquisition

If you encounter a system that has a mounted TrueCrypt drive, it is imperative that you capture the contents of the encrypted drive before shutting down the system. Once the system is shutdown, the contents will be inaccessible unless you have the proper encryption key generated by a user's password. You may also need an additional datafile.

Attacks

The only option for acquiring the content of a dismounted TrueCrypt drive is to do a brute-force password guessing attack. AccessData's Password Recovery Toolkit and Distributed Network Attack (DNA) can both perform such an attack, but DNA is faster. Another solution is unprotect.info that can brute-force password to the file-based encrypted volumes.

TrueCrypt also supports keyfiles (it uses the first 1024 kilobytes of any file, but can also use it's PRNG to generate such keys). It is important to look for anything that might be used as a keyfile (such as a 1024k file on a USB stick).

Hidden volumes

Hidden volume is a volume hidden within the free space of another TrueCrypt volume. Even when the outer volume is mounted, it is hard to prove whether there is a hidden volume or not.

When a hidden volume is mounted, the operating system and third-party applications may write to non-hidden volumes information about the data stored in the hidden volume (e.g. filenames). It is important to look for such kind of information.

Previous versions of encrypted containers may be found in the journaling filesystems. It is important to track any changes within the free space of the outer container to detect presence of a hidden container.

Hidden Operating Systems

Hidden operating system is a system that is installed in a hidden TrueCrypt volume.

It is possible to detect network-enabled hidden operating systems by matching downloaded content (from a network dump) with data on a possible decoy system.

Investigator can also detect boot times by searching network dumps for IP packets with low IDs (only if Windows system is permanently connected to a LAN) and TCP timestamps.

External Links