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Steganography Ryan Albright
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Presentation Overview
Steganography -What is Steganography -History of Steganography -Types of Steganography -Steganography Tools -Steganography Today Steganalysis -What is Steganalysis -Problems Questions
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Steganography - Definition
-From the Greek word “steganos” meaning “covered” and the Greek word “graphie” meaning “writing” -The process of hiding secret messages within an ordinary message and extracting it at its destination -Anyone else viewing the message will fail to know that it contains hidden/encrypted data
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Steganography – History
Ancient Romans -write between line using invisible ink -fruit juices, milk, and urine -when heated, messages appear Store messages on messenger's head
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Steganography - History
During WWII Germans developed Microdot -secret message photographically reduced to size of period -affixed as the . in the letter i -large amounts of printed data, including drawings Laser Printers -hide short binary message in a document 0 = standard space 1 = 1/300 inch more than usual
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Steganography - Principles
Steganography is based on two principles -Files that contain digitized images or sound can be altered to a certain extent without loosing their functionality unlike other types of data that have to be exact in order to function properly. -The other principle deals with the human inability to distinguish minor changes in image color or sound quality, which is especially easy to make use of in objects that contain redundant information, be it 16-bit sound, 8-bit or even better 24-bit image.
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Steganography – Text (Null Ciphers)
-Message sent by German spy in WWII Apparently neutral's protest is thoroughly discounted and ignored. Isman hard hit. Blockade issue affects pretext for embargo on by products, ejecting suets and vegetable oils. -Take the second letter in each word Pershing sails from NY June 1.
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Steganography – Spam Text
Dear Friend , This letter was specially selected to be sent to you ! We will comply with all removal requests ! This mail is being sent in compliance with Senate bill 1621 ; Title 5 ; Section 303 ! Do NOT confuse us with Internet scam artists . Why work for somebody else when you can become rich within 38 days ! Have you ever noticed the baby boomers are more demanding than their parents & more people than ever are surfing the web ! Well, now is your chance to capitalize on this ! WE will help YOU sell more & SELL MORE . You can begin at absolutely no cost to you ! But don't believe us ! Ms Anderson who resides in Missouri tried us and says "My only problem now is where to park all my cars" . This offer is 100% legal . You will blame yourself forever if you don't order now ! Sign up a friend and your friend will be rich too . Cheers ! Dear Salaryman , Especially for you - this amazing news . If you are not interested in our publications and wish to be removed from our lists, simply do NOT respond and ignore this mail ! This mail is being sent in compliance with Senate bill 2116 , Title 3 ; Section 306 ! This is a ligitimate business proposal ! Why work for somebody else when you can become rich within 68 months ! Have you ever noticed more people than ever are surfing the web and nobody is getting any younger ! Well, now is your chance to capitalize on this . We will help you decrease perceived waiting time by 180% and SELL MORE . The best thing about our system is that it is absolutely risk free for you ! But don't believe us ! Mrs Ames of Alabama tried us and says "My only problem now is where to park all my cars" . We are licensed to operate in all states ! You will blame yourself forever if you don't order now ! Sign up a friend and you'll get a discount of 20% ! Thanks ! Dear Salaryman , Your address has been submitted to us indicating your interest in our briefing ! If you no longer wish to receive our publications simply reply with a Subject: of "REMOVE" and you will immediately be removed from our mailing list . This mail is being sent in compliance with Senate bill 1618 , Title 6 , Section THIS IS NOT A GET RICH SCHEME . Why work for somebody else when you can become rich within 17 DAYS ! Have you ever noticed more people than ever are surfing the web and more people than ever are surfing the web ! Well, now is your chance to capitalize on this ! WE will help YOU turn your business into an E-BUSINESS and deliver goods right to the customer's doorstep ! You are guaranteed to succeed because we take all the risk ! But don't believe us . Ms Simpson of Wyoming tried us and says "Now I'm rich, Rich, RICH" ! We assure you that we operate within all applicable laws . We implore you - act now ! Sign up a friend and you'll get a discount of 50% . Thank-you for your serious consideration of our offer .
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Steganography – Spam Text
Meet at Main and Willard at 8:30 -Message looks like typical spam, which is generally ignored and disregarded -Created at Spam Mimic, a web site that converts blocks of text into spam -Uses grammar based mimicry -Reader will learn nothing by looking at the spacing or misspellings -Zeros and ones are encoded by the choice of words
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Steganography – Digital Images
Hiding Text -Stored as array of colored dots, pixels -Each pixel has three numbers associated with it, one for Red, Green, Blue -Each number is stored as 8 bits -Picture can still look good if the 4 least significant bits are altered, a change of 16 in the color’s value -Can hide 1.5 letters per pixel -A 640x480 image can hold over 400,000 characters
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Steganography – Digital Images
Word document containing the text: “Meet me at 3:00PM at 310 Roble Drive Indiana PA 15701”
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Steganography – Digital Images
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Steganography – Digital Images
Hiding Images -Easier than hiding text -Line pictures up pixel by pixel -Take the 4 most significant bits of the secret photo -Place them in the 4 least significant bits of the carrier photo
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Steganography – Digital Images
-The new values of the images are strongly patterned, so they are easily recognizable. -The hidden image would be easily recognized by statistical analysis -The final step is to make the message look random before hiding it -Encode the message before hiding it -Spread information randomly over photo using random number generator
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Steganography – Digital Images
Carrier File Secret Picture
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Steganography – Digital Image
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Steganography – Audio & Video
-Least Significant Bit -modification usually won’t create noticeable audible changes -Take advantage of human limitations -encode messages using frequencies inaudible to human ears (above 20,000 hz) -Use musical tones -F tone = 0’s C tome =1’s -compose piece around secret message
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Steganography - Tools -S-Tools -EzStego -Jpeg Hide & Seek
-JSteg Shell 2.0 -OutGuess -Multiple Others
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Steganography – Digital Watermaking
Create invisible digital marks in images and audio files -Carry copyright information -Prevents theft of material
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Steganography – Al-Qaida
-Believed that Osama Bin-Laden and Al-Qaida hide terrorist plots on sports chat rooms and porn sites. -Difficult to intercept hidden images -2 billion web sites -28 billion images
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Steganalysis - Definition
-the art of and science of detecting data in hidden signals -the goal of steganalysis -identify suspected packages -determine if they contain hidden data -recover the data, if possible
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Steganalysis - Problems
-suspected file may or may not have data hidden in them in the first place -the data may have been encrypted before it was placed in the carrier file -some files may have irrelevant data encoded in them -unless you completely recover the data, you can’t be sure there was hidden data in the first place
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Steganalysis - Study University of Michigan Study
-scanned over 2 million images on Ebay -failed to find a single hidden message
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Questions
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