Version Information

Security Model 
Note to security researchers: If you intend to report a security issue or publish an attack on 
TrueCrypt, please make sure it does not disregard the security model of TrueCrypt described 
below. If it does, the attack (or security issue report) will be considered invalid/bogus.
TrueCrypt is a computer software program whose primary purposes are to: 
•
Secure data by encrypting it before it is written to a disk. 
•
Decrypt encrypted data after it is read from the disk. 
TrueCrypt does 
not
: 
•
Encrypt or secure any portion of RAM (the main memory of a computer). 
•
Secure any data on a computer
*
if an attacker has administrator privileges
†
under an 
operating system installed on the computer. 
•
Secure any data on a computer if the computer contains any malware (e.g. a virus, Trojan 
horse, spyware) or any other piece of software (including TrueCrypt or an operating system 
component) that has been altered, created, or can be controlled, by an attacker. 
•
Secure any data on a computer if an attacker has physical access to the computer before 
or while TrueCrypt is running on it. 
•
Secure any data on a computer if an attacker has physical access to the computer between 
the time when TrueCrypt is shut down and the time when the entire contents of all volatile 
memory modules connected to the computer (including memory modules in peripheral 
devices) have been permanently and irreversibly erased/lost. 
•
Secure any data on a computer if an attacker can remotely intercept emanations from the 
computer hardware (e.g. the monitor or cables) while TrueCrypt is running on it (or 
otherwise remotely monitor the hardware and its use, directly or indirectly, while TrueCrypt 
is running on it). 
•
Secure any data stored in a TrueCrypt volume
‡
if an attacker without administrator 
privileges can access the contents of the mounted volume (e.g. if file/folder/volume 
permissions do not prevent such an attacker from accessing it). 
•
Preserve/verify the integrity or authenticity of encrypted or decrypted data. 
•
Prevent traffic analysis when encrypted data is transmitted over a network. 
•
Prevent an attacker from determining in which sectors of the volume the content changed 
(and when and how many times) if he or she can observe the volume (dismounted or 
mounted) before and after data is written to it, or if the storage medium/device allows the 
attacker to determine such information (for example, the volume resides on a device that 
saves metadata that can be used to determine when data was written to a particular 
sector). 
•
Encrypt any existing unencrypted data in place (or re-encrypt or erase data) on 
devices/filesystems that use wear-leveling or otherwise relocate data internally. 
•
Ensure that users choose cryptographically strong passwords or keyfiles. 
* In this section (
Security Model
), the phrase “data on a computer” means data on internal and external storage 
devices/media (including removable devices and network drives) connected to the computer
.
†
In this section (
Security Model
), the phrase “administrator privileges” does not necessarily refer to a valid administrator 
account. It may also refer to an attacker who does not have a valid administrator account but who is able (for example, 
due to improper configuration of the system or by exploiting a vulnerability in the operating system or a third-party 
application) to perform any action that only a user with a valid administrator account is normally allowed to perform (for 
example, to read or modify an arbitrary part of a drive or the RAM, etc.) 
‡
“TrueCrypt volume” also means a TrueCrypt-encrypted system partition/drive (see the chapter 
System Encryption
). 

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84 
•
Secure any computer hardware component or a whole computer. 
•
Secure any data on a computer where the security requirements or precautions listed in the 
chapter 
Security Requirements and Precautions
 are not followed. 
•
Do anything listed in the section 
Limitations 
(chapter 
Known Issues & Limitations
). 
Under 
Windows
, a user without administrator privileges can (assuming the default TrueCrypt and 
operating system configurations): 
•
Mount any file-hosted TrueCrypt volume provided that the file permissions of the container 
allow it. 
•
Mount any partition/device-hosted TrueCrypt volume. 
•
Complete the pre-boot authentication process and, thus, gain access to data on an 
encrypted system partition/drive (and start the encrypted operating system). 
•
Skip the pre-boot authentication process 
(this can be prevented by disabling the option 
Settings
> 
‘
System Encryption
’ > ‘
Allow pre-boot authentication to be bypassed by pressing the Esc key
’; note that this 
option can be enabled or disabled only by an administrator)
. 
•
Dismount, using TrueCrypt, (and, in the TrueCrypt application window, see the path to and 
properties of) any TrueCrypt volume mounted by him or her. However, this does not apply 
to ‘system favorite volumes’, which he or she can dismount (etc.) regardless of who 
mounted them 
(this can be prevented by enabling the option 
Settings
> ‘
System Favorite Volumes
’ > ‘
Allow 
only administrators to view and dismount system favorite volumes in TrueCrypt
’; note that this option can be 
enabled or disabled only by an administrator)
. 
•
Create a file-hosted TrueCrypt volume containing a FAT or no file system (provided that the 
relevant folder permissions allow it). 
•
Change the password, keyfiles, and header key derivation algorithm for, and restore or 
back up the header of, a file-hosted TrueCrypt volume (provided that the file permissions 
allow it). 
•
Access the filesystem residing within a TrueCrypt volume mounted by another user on the 
system (however, file/folder/volume permissions can be set to prevent this). 
•
Use passwords (and processed keyfiles) stored in the password cache 
(note that caching can 
be disabled; for more information see the section 
Settings -> Preferences
, subsection 
Cache
passwords in 
driver memory
)
. 
•
View the basic properties (e.g. the size of the encrypted area, encryption and hash 
algorithms used, etc.) of the encrypted system partition/drive when the encrypted system is 
running. 
•
Run and use the TrueCrypt application (including the TrueCrypt Volume Creation Wizard) 
provided that the TrueCrypt device driver is running and that the file permissions allow it. 
Under 
Linux
, a user without administrator privileges can (assuming the default TrueCrypt and 
operating system configurations): 
•
Create a file-hosted or partition/device-hosted TrueCrypt volume containing a FAT or no file 
system provided that the relevant folder/device permissions allow it. 
•
Change the password, keyfiles, and header key derivation algorithm for, and restore or 
back up the header of, a file-hosted or partition/device-hosted TrueCrypt volume provided 
that the file/device permissions allow it. 
•
Access the filesystem residing within a TrueCrypt volume mounted by another user on the 
system (however, file/folder/volume permissions can be set to prevent this). 
•
Run and use the TrueCrypt application (including the TrueCrypt Volume Creation Wizard) 
provided that file permissions allow it. 
•
In the TrueCrypt application window, see the path to and properties of any TrueCrypt 
volume mounted by him or her. 

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Under