Steganography Cyber Security Camp, July 22, 2015 Rodrigo Sardiñas Dr. David Umphress William Frazier

What is Steganography 2

The art of covered or hidden writing. Steganos – Greek word meaning “covered” Graphy – Latin word meaning “writing” or “drawing” Thousands of years old – Tattoos, symbols, contextual clues/jargon, bunnies Difficult to detect (if you don’t know its there) 3

What Steganography is Not Cryptography – Kryptos = secret or hidden – Graphein/Logia = writing/study – The art of writing or solving codes. – Hide the meaning, not the message Steganography – Hide the message, not the meaning Can both be used to obscure data 4

Example 1 Covered or concealment ciphers – Use null cipher to hide message according to some prearranged set of rules Frank is not doing my editing. Hidden message: “Find me” 5

Activity 1 At your table, devise your own concealment cipher strategy. (5 minutes) Use that strategy to hide a message. (3 min) Class will have several minutes to try to decipher each group’s message. – Prize for group with most correct guesses – Prize for group with most elaborate or creative strategy 6

Types of Steganography Insertion Substitution Generation 7

Insertion (Injection) Hide data in sections of a file that are not processed – Comments section in HTML file – After EOF marker in regular file – Metadata section of file No modification of relevant data Will add to original file size No limit to how much can be hidden Potential to detect if compared to original 8

Example 2 Steganography via injection OriginalEdited in Notepad++ 9

Activity 2 (text only) Open an image using notepad++ Write a message at the bottom of the file Open the image normally to view it Experiment with writing messages at various locations in the image (in notepad++) to see what happens Discuss results of inserting messages in places other than at the end – What happens when you add text to beginning? – What about somewhere in the middle? 10

Activity 3 (files) Create file(s) (any files, text, word, etc…) Zip files up using built-in windows zip command (send to -> zip file) Place zip and an image in same folder Open command in current directory – Shift + right click -> open command prompt here copy /b [name of picture].jpg + [name of zip file].zip [new name for picture].jpg View new image normally Change file extension to.zip to view archive contents 11

Substitution Make minor changes in data such that user doesn’t notice change No change in file size Limited in how much can be hidden Potential to detect if compared to original 12

Example 3 Least Significant Bit Substitution Original Modified 13

Activity 5 Open a web browser and go to the following URL: – ganography.php ganography.php Follow instructions to upload any image Type hidden message Do not enter a password (no encryption) Download image with message inside Open in notepad++ to see if you can find message Go back to website and follow instructions to show message 14

End of Session 1 Lunch 15

Generation Create new file from carrier (file hiding the data) and hidden data file using some algorithm No limit to how much can be hidden Cannot be compared to original since a brand new “original” file is created 16

Example 5 Use custom algorithm to hide data 17 Created image Message hidden in audio generated from image

Activity 4 Do Together (part 1) Use Gimp to create hidden message – Create new image – Change background color to black – Create text in image (use white text) – Export image as JPEG 18

Activity 4 Do Together (part 2) Use coagula to convert JPEG to audio (.wav) file – Open JPEG in coagula – Select “render without blue” This should create coagula.wav in current folder 19

Activity 4 Do Together (part 3) Use Audacity to view message – Open coagula.wav in audacity – Select Spectrogram option to view hidden message 20

Activity 5 (part 1) Use OpenPuff to Hide, encrypt, and distract Hide data – Choose 3 different passwords (write them down) 2 for crypto, 1 for scrambling – Select data to hide From secret data folder – Select multiple carriers (.mp3,.jpg,.pdf, ect…) From carrier folder – Sort carriers – Select noise level – Add Decoy – Enter 3 different passwords – Choose output folder(s) 21

Activity 5 (part 2) 22

Activity 5 (part 3) Use OpenPuff to Hide, encrypt, and distract Unhide data – Enter all passwords If you want to unhide decoy, enter decoy passwords If you want to unhide data, enter data passwords – Browse to folder with previous carriers and choose correct ones – Sort carriers in same order as before – Select same noise level as before – Verify data is correct 23

Activity 5 (part 4) 24

Who Uses Steganography Spies and terrorists – dyn/content/article/2010/06/30/AR html dyn/content/article/2010/06/30/AR html Commercial and Government – Suggest to use with encryption – Watermarking Hackers – detection/hackers-exfiltrating-data-with-video- steganography-via-cloud-video-services/ detection/hackers-exfiltrating-data-with-video- steganography-via-cloud-video-services/ All of us after this workshop! 25

Interesting Application of Steganography -the-man-who-solved-the-mysterious-cicada puzzle/ -the-man-who-solved-the-mysterious-cicada puzzle/ 26

A Keystone in Building a Better Future for All 27