Hello,

We noticed you're browsing in private or incognito mode.

To continue reading this article, please exit incognito mode or log in.

Not an Insider? Subscribe now for unlimited access to online articles.

Christopher Mims

A View from Christopher Mims

Russian Spies' Use of Steganography Is Just the Beginning

Given the universal applicability of steganographic principles, next time the FBI might not be so lucky.

  • July 13, 2010

One of the ways the 10 Russian spies that the U.S. just sent home to the motherland in a spy swap communicated with their handlers was via steganography - the act of embedding secret information in some other signal.

In this case, the spies were embedding messages in images that were then uploaded to public websites. The messages weren’t encrypted - just invisible to the naked eye; lost in the endless stream of communications transmitted daily through the web.

Here’s the thing about steganography: it doesn’t take much to implement it in almost any signal you can imagine - and doing so is surprisingly trivial. There are over 600 different known steganography programs, according to digital forensics firm WetStone Technologies, and the one the Russian spies used was custom-made.

Indeed, it’s so easy to write a steganography program that Jon McLoone, head of international business and strategic development at Wolfram, wrote one in Mathematica with just a handful of lines of code. He helpfully points out that his version, unlike the one the spies were using, isn’t likely to crash.

But this is just the beginning: the principles of steganography can be applied even to continuous communications, such as conventional wireless networks. Using this approach, Krzysztof Szczypiorski and Wojciech Mazurczyk figured out how to pour up to a megabyte per second into an open wireless network.

Steganography can also be implemented in sound files and VoIP protocols. Here’s a scenario from Stegano.net, the leading site on steganography: “An employee of an electronic equipment factory uploads a music file to an online file-sharing site. Hidden in the MP3 file (Michael Jackson’s album Thriller) are schematics of a new mobile phone that will carry the brand of a large American company. Once the employee’s Taiwanese collaborators download the file, they start manufacturing counterfeit mobile phones essentially identical to the original–even before the American company can get its version into stores.”

Steganography works because it’s possible to hide secret data in all the wasted or less-essential bits in any communication. All files have what are known as least significant bits - they’re the part of any binary number that, when lost, does the least to change the value of the value it represents. (By analogy, the least significant digit of decimal integer 43.218 is 8, and if you lose it you’ve hardly changed the value of that number for most purposes.)

These bits are especially disposable when you’re dealing with files that only have to be perceived by a human - throwing out or messing with these bits is the basis of much of the compression technology we rely on to make it easier to transmit multimedia, because we simply don’t notice that they’ve gone missing.

In a way, then, a lot of the best hiding places for secret information on our networks are a product of our imperfect - or too-perfect - sensory systems: either we aren’t noticing an awful lot, or we’re very good at filtering out noise, depending on how you look at it. If we were all automatons with absolutely perfect perception, it would be much tougher to find any least significant bits into which to dump coded messages.

Follow Christopher Mims on Twitter, or contact him via email.

Want to go ad free? No ad blockers needed.

Become an Insider
Already an Insider? Log in.
Want more award-winning journalism? Subscribe and become an Insider.
  • Insider Plus {! insider.prices.plus !}* Best Value

    {! insider.display.menuOptionsLabel !}

    Everything included in Insider Basic, plus the digital magazine, extensive archive, ad-free web experience, and discounts to partner offerings and MIT Technology Review events.

    See details+

    Print + Digital Magazine (6 bi-monthly issues)

    Unlimited online access including all articles, multimedia, and more

    The Download newsletter with top tech stories delivered daily to your inbox

    Technology Review PDF magazine archive, including articles, images, and covers dating back to 1899

    10% Discount to MIT Technology Review events and MIT Press

    Ad-free website experience

  • Insider Basic {! insider.prices.basic !}*

    {! insider.display.menuOptionsLabel !}

    Six issues of our award winning print magazine, unlimited online access plus The Download with the top tech stories delivered daily to your inbox.

    See details+

    Print Magazine (6 bi-monthly issues)

    Unlimited online access including all articles, multimedia, and more

    The Download newsletter with top tech stories delivered daily to your inbox

  • Insider Online Only {! insider.prices.online !}*

    {! insider.display.menuOptionsLabel !}

    Unlimited online access including articles and video, plus The Download with the top tech stories delivered daily to your inbox.

    See details+

    Unlimited online access including all articles, multimedia, and more

    The Download newsletter with top tech stories delivered daily to your inbox

/3
You've read of three free articles this month. for unlimited online access. You've read of three free articles this month. for unlimited online access. This is your last free article this month. for unlimited online access. You've read all your free articles this month. for unlimited online access. You've read of three free articles this month. for more, or for unlimited online access. for two more free articles, or for unlimited online access.