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Evidence of Steganography in Real Criminal Cases
Posted by
Zonk
on Sat Oct 20, 2007 07:14 AM
from the not-just-a-numb3rs-plot dept.
from the not-just-a-numb3rs-plot dept.
ancientribe writes "Researchers at Purdue University have found proof that criminals are making use of steganography in the field. Steganography is the stealth technique of hiding text or images within image files. Experts say that the wide availability of free point-and-click steganography tools is making the method of hiding illicit images and text easier to use. Not everyone is convinced; some security experts such as Bruce Schneier have dismissed steganography as too complex and conspicuous for the bad guys to bother using, especially for inside corporate espionage: 'It doesn't make sense that someone selling out the company can't just leave with a USB.'"
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"Security Expert" (Score:3, Insightful)
From the article (Score:3, Informative)
But Bruce Schneier, CTO of BT Counterpane, disagrees. He says steganography doesn't make sense as an insider threat. It's much easier to just suck the data off onto a USB thumb drive and walk out of the building.
That seems to make a little more sense. They still don't quote Schneier directly, but his general conclusion seems valid. The purpose of steganography is to provide a clandestine channel, in part to avoid traffic analysis. If the data embedded through steganography is also encrypted, it would be very hard to detect. That's why this study is significant. I'll wait until it's farther along than its "early phases" before I draw any substantive conclusions, though.
Re:"Security Expert" (Score:5, Funny)
Who calls USB keys "USB"s like one of my computer illiterate friends. Or is this some new kind of slang that I am not aware of.
Is there a common standard term for them yet? People I know call them variously "USB drive", "USB key", "Key drive", "Pen Drive", "Memory Stick", "USB stick", "USB..um..memory..thing", or "You know, that thing that goes in the USB slot that you keep stuff on". I personally call mine 'Steve' to avoid the confusion.
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Re:"Security Expert" (Score:4, Funny)
In a Spanish-speaking office I was trying to guess at the name and called it a palito, which literally means "little stick." It took about two minutes for the laughter to die down, and then I learned that palito is slang for dick.
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Re:"Security Expert" (Score:5, Funny)
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Re:"Security Expert" (Score:5, Funny)
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Re:"Security Expert" (Score:4, Funny)
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Old news though (Score:3, Interesting)
Steganography is also in use by some media producers, I've heard cases where demo tracks have included some randomness that is later detectable to find the source of whoever leaked the track (each person on the initial review got a different copy of the randomness).
Re: (Score:3, Interesting)
The best implementation (Score:5, Funny)
First the program takes the target JPG (which you want to be very large), and treats it as random noise. Simply a field of random zeros and ones. Then, within that vast field, the program selects a pattern or frequency to place variations in the noise pattern.
The variations in the noise pattern act as a beacon - sort of a signal that the payload is coming. Common variations include mathematical pulses at predictable intervals - say something that would easily be recognizable by a 5th-grader, like say a pattern of prime numbers.
Then it layers in a second layer, nested within the main signal. Some bits are bits to tell how to interpret the other bits. Use a gray scale with standard interpolation. Rotate the second layer 90 degrees. Make sure there's a string break every 60 characters, and add an auxiliary sideband channel. Make sure that the second layer is zoomed in sufficiently, and using a less popular protocol language, so that upon first glance it's not easily recognizable.
Here's the magical part: It then adds in a third layer. Sort of like in ancient times when parchment was in short supply people would write over old writing... it was called a palimpsest. Here you can catalog over 10,000 "frames" of data, which can communicate any message that you want.
Further details on this method can be found here. [imsdb.com]
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looks like something doesn't work properly (Score:5, Informative)
Maybe this really means that the software available for this type of use just doesn't work very well?
Re:looks like something doesn't work properly (Score:5, Informative)
FYI you can detect the presence of steganographed information by statistical means (http://en.wikipedia.org/wiki/Steganalysis).
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Debunking steganography (Score:5, Interesting)
Specially if the marketing blurb mentions "military grade" (translation : triple AES is used to store the password. The reader software inputs a password from the user and if it matches the hash... the soft proceeds extracting the otherwise clear, non crypted and un-obfuscated payload).
So while it *is* possible to design actually working steganography, if a would-be pedo-terrorist-criminal tries to google for stenographic software, he'll most likely land on useless software.
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These must be freshman researchers (Score:5, Informative)
To those versed in statistics or the scientific method, find the flaw in this statement (as taken from the article):
"with the little data we have so far, we are finding that there's a strong correlation between criminal activity and at least the installation of steganography programs on those [confiscated] computers"
With the little data I have so far, I think the researchers are pulling our leg.
Re:These must be freshman researchers (Score:4, Funny)
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Re:These must be freshman researchers (Score:5, Informative)
Considering that Bruce Schneier has been around the block for a loooong time and has written several good books on cryptography and computer security, including the seminal "Applied Cryptography" (which needs a new edition! Hint hint if you're out there, Bruce!), I think it's far more likely that you have no idea who Bruce Schneier is. I'm sure that by "conspicuous" he's referring to the fact that steganography can be detected through statistical analysis, and the fact that most steganography software is crap.
Being inconspicuous isn't the definition of steganography any more than being secure is the definition of cryptography (Ceasar Ciphers, ROT-13, DES). They're both just important traits that make their respective -graphies more effective. Bruce's statement is referring to the sad state of pretty much all of the steganographic software out there right now, because it's pretty much all the security equivalent to sticking your super secret files in a hidden directory and hoping the secret police just overlook it.
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I doubt it happens on a large scale (Score:5, Informative)
Installation of steganography tools != using those tools in practice. If someone is looking to conceal data, they may be grabbing anything out there that stands a remote chance of being helpful. Sort of like how in the early days students would have all kinds of music players and point-to-point file exchange programs, looking for ones that would do what they wanted or had what they wanted.
James Wingate, director of the steganography analysis & research center at Backbone Security, and a vice president there, says the use of steganography is on the rise, and it could be used for things like transporting malware.
"Some would call me 'Chicken Little,' but I fervently and passionately believe criminal activity is being conducted with steganography... We do know it's being used to conceal child pornography," Wingate says. "
When someone "fervently and passionately" believes something, particularly something related to a day-to-day project where one's institution stands a good chance of increased funding if what you believe is true, that's a good indication that you need to look hard for real, reproducible evidence that will stand up to rigorous peer review. Nor should concealing those types of images be surprising - unfortunately there seem to be a large number of sickos out there with this stuff, and probably every data-concealing program ever written has been used to conceal it (or try to). More to the point, is it in WIDE use?
I agree that a USB stick is a much more plausible attach vector for a company insider (no "hey what was that huge surge of email traffic with images?" signatures for IT to poke their noses into, just for starters.) If someone wants to hide data on their machine, I would think any of the various harddrive encryption techniques would both be simpler and much more effective.
I remember looking around at steganography tools some years back for other purposes (watermarking images people were considering contributing to a collectibles website) and my conclusion was that the most practical use of the techniques was to store information one WANTED to be found - another way to put metadata into an image so you could later figure out additional information about it (say, for a baseball card certified by a company you could add the certification information using steganography to ensure later availability of the information even without the website context, unless the image was compressed or otherwise distorted. It didn't and doesn't strike me as anything that can be used for anything uniquely evil or even uniquely practical (real image metadata is most likely a better place for useful info, and hiding information in it is an iffy proposition at best.
Remember, just because non-government researchers can't cover all 800+ programs doesn't mean someone like the NSA with large funding and budgets couldn't throw resources at it until they had all of them covered. Somebody will probably use it, but someone will use virtually every possible technique to do something at least once in the vastness of the Internet so that's not a very interesting statement. The interesting question is will a lot of people use it, and I just can't see it being worth the trouble.
get over it (Score:5, Insightful)
Right now, police can still detect the steganography tools, but those will start to be hidden as well. Encrypted, hidden data can be added to MP3s, MPEG4s, PDFs, scans, executables, random leftover noise on the disk. It can be hidden on microSD cards, printed on paper, and hidden on DVDs.
There is no way governments or companies can stop covert communications of data. Get over it and stop making laws that are unenforceable but give police and governments ever more tools to abuse their powers.
Re:get over it (Score:5, Interesting)
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Summary of Article (Score:5, Funny)
New Purdue University research shows steganography, long considered a minor threat, may be on the rise
OCTOBER 18, 2007 | 6:00 PM
By Kelly Jackson Higgins Senior Editor, Dark Reading
Until recently, steganography, the stealth technique of hiding text or images within image files, has mostly been considered too complex -- and conspicuous -- to be much of a threat. But some forensics experts now worry that the bad guys are starting to use the tactic more frequently, especially in child pornography and identity theft trafficking.
There are an estimated 800 or so steganography tools available online, many of them free and with user-friendly graphical user interfaces and point-and-click features. This broad availability making steganography more accessible and easier to use for hiding and moving stolen or illicit payloads, experts say.
Security experts to date have mostly dismissed steganography as a mainstream threat, relegating it to the domain of spooks and the feds. Their skepticism has been well-founded: The few studies that have searched for images hiding steganographic messages have come up empty-handed.
One thing I don't get (Score:4, Insightful)
For example, if "teh terrist" wanted to send a message like "attack now", why couldn't the message be given via a pre-arranged signal -- say the image shows Osama wearing a silver watch for "It's go time", and a gold watch for "wait out the Americans". No one can detect a "hidden message" because there is none.
You could do the same for other things even if you don't use USB (which would probably be easiest in a workplace). How about plain old pencil and paper? Just write down the information, put it in a device called an "envelope", write down the physical address of the guy you're sending it to, and drop it off in the post office. It's virtually untraceable, and would work even if the IT guys turn off the USB ports.
This is just the first stage ... (Score:5, Funny)
Stenography probably not used for bulk data xfer (Score:3, Interesting)
A point to note is that the criminals using stenography are probably not using it to transfer large quantities of information, but merely communicating small very private messages. This might include links to web servers, credit card numbers or meeting/payment instructions. It is unlikely to require more than a few hundred bytes of data.
While Schneier is correct that corporate theft is best accomplished with USB drives or even your corporate laptop, the criminals using stenographic software are probably not using it for their bulk transfers of information, but rather pointers or encryption keys to information transfered by other means.
Comparing the number of web pages against the number of child pornographers who might be hiding stenographic in online images makes Purdue's attempt to crawl the web in search for stenographic data seem futile.
Data transfers by stenography have to be pre-arranged in advance by some other communication method, otherwise how would sender and receiver know how to encrypt/decrypt their messages? If your interest is in stopping crime, then this is the weakest link and should be the focus of your detective work.
and now THINK for a second. (Score:3, Insightful)
How big is that picture of your daughter? I seen a real world example of it. A 4mb image, that somehow only seemed to result in a small photo of about a 100x100 pixels. Yeah, that ain't suspicious AT ALL. Doesn't set of any alarm bells. Nope.
That is the entire problem with the idea, how do you get enough information inside and still not raise suspicion. It is different for coded messages, keep the code small and it can easily fit but to leak information, you need to start including megabytes of documents i
Re:Just because you think it doesn't make sense... (Score:4, Funny)
(slammed against the wall)
"Bro don't tase me, don't tase me! Br-clickclickclickclickclick"
Welcome to the NEW America.
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