Commentary

George Hulme
 

Encrypted Disks At (Some) Risk To Eavesdroppers

Whether you are using Windows Vista BitLocker, Mac OS X FileVault, Linux-based dm-crypt, or open source disk encryption software TrueCrypt - your data could be at risk to snoops, researchers have found. While it is troubling news, all is not lost.

Whether you are using Windows Vista BitLocker, Mac OS X FileVault, Linux-based dm-crypt, or open source disk encryption software TrueCrypt - your data could be at risk to snoops, researchers have found. While it is troubling news, all is not lost.As reported earlier today by my associate Thomas Claburn, researchers from Princeton University, the Electronic Frontier Foundation, and Wind River Systems have found a way to find disk encryption keys in system RAM.

This means, if you leave your system in either "sleep" or "hibernate" mode, it has been proven that the keys used to encrypt and decrypt files or an entire drive can be found -- still resident in memory -- and used to access private data at will.


More Security Insights

White Papers

More >>

Reports

More >>

Webcasts

More >>

Also troubling is that the researchers warn that this attack could be used to snoop on SSL sessions (how Web site communication is commonly secured in transit to and from your PC) as well as DRM technologies (such as is used for eBooks and music files).

It's important to note that it's not the encryption scheme, which is the mathematical algorithm used to scramble legible information into gibberish, that has been proven vulnerable. It's how all data is stored in RAM that creates the condition. And by using software to scan RAM for private encryption keys, after either booting from across a network, external, or USB drive, the secret keys can be uncovered, for a short period of time, after the machine has been turned off.

A system still getting power, such as in hibernate mode, is vulnerable to this attack.

What all of this means is that walking away from your system in an office, hotel room, or any place you don't feel secure: relying on the system's automatic screen saver password, or going into sleep mode isn't safe enough. You have to turn the system off, and if you're really concerned, wait a few minutes until the RAM has no more power. What's more, the researchers found, is that the length of time that residual files remain available in RAM memory, including crypto keys, can be extended through the use of giving DRAM modules a cold blast of compressed air.

None of this is going to change my behavior much. I'm still going to continue using TrueCrypt. Only I'll now shut my system off when leaving it unattended in a hotel room, or other place I don't feel secure. And I'll keep an eye out for strangers rapidly approaching me armed with little more than a can of GasDuster.


Related Reading




Currently we allow the following HTML tags in comments:

Single tags

These tags can be used alone and don't need an ending tag.

<br> Defines a single line break

<hr> Defines a horizontal line

Matching tags

These require an ending tag - e.g. <i>italic text</i>

<a> Defines an anchor

<b> Defines bold text

<big> Defines big text

<blockquote> Defines a long quotation

<caption> Defines a table caption

<cite> Defines a citation

<code> Defines computer code text

<em> Defines emphasized text

<fieldset> Defines a border around elements in a form

<h1> This is heading 1

<h2> This is heading 2

<h3> This is heading 3

<h4> This is heading 4

<h5> This is heading 5

<h6> This is heading 6

<i> Defines italic text

<p> Defines a paragraph

<pre> Defines preformatted text

<q> Defines a short quotation

<samp> Defines sample computer code text

<small> Defines small text

<span> Defines a section in a document

<s> Defines strikethrough text

<strike> Defines strikethrough text

<strong> Defines strong text

<sub> Defines subscripted text

<sup> Defines superscripted text

<u> Defines underlined text

InformationWeek encourages readers to engage in spirited, healthy debate, including taking us to task. However, InformationWeek moderates all comments posted to our site, and reserves the right to modify or remove any content that it determines to be derogatory, offensive, inflammatory, vulgar, irrelevant/off-topic, racist or obvious marketing/SPAM. InformationWeek further reserves the right to disable the profile of any commenter participating in said activities.

Disqus Tips To upload an avatar photo, first complete your Disqus profile. | View the list of supported HTML tags you can use to style comments. | Please read our commenting policy.
T-Shirt Giveaway T-Shirt Giveaway: Each week we're selecting one great comment from our readers. The author of the comment will receive an InformaitonWeek Community t-shirt. So get posting!
Subscribe to RSS

Resource Links