Steganography: How to Hide Secret Information inside JPG Image Files?

Last year, there were several publications in press that al-Qaeda operatives were sending out encrypted messages to the terrorist groups members by hiding them inside digital photographs on eBay. While there no definite proof that this claim is justified, it is quite easy to hide any other file or group of files inside a JPEG image. You can place video clips, pdf, mp3, Office documents, zipped files, webpage or any other file format without special software and encoding knowledge. Any stranger that will get the image and will open it in either a photo editing software or as a thumbnail inside Windows Explorer, there will be no visible indication that the open file is more than just a regular image.

Let’s learn this simple trick, available with tools embedded in Operating System.

Step 1: Choose the secret file or groups of files, you want to embed in the image. For multiple files, compress them in a single archive with locking password if needed additional level of the data security.

Step 2: Select any image JPG file, where your data will be hidden.

Step 3: For simplifying the application, move the two files (data file and image file) directly on the root of your main drive C:

Step 4: Open Command Prompt (Start - All Programs - Accessories - Command Prompt).

Step 5: Type in the DOS-like window “cd \” to get to the drive, where the files moved on the step 3.

Step 6: Type “copy /B original.jpg + secretfiles.zip new.jpg”, where “original.jpg” represents the image file, you are planning to use as your data safe, “secretfiles.zip” (or any other data, video, audio, or text file) is the archive or file you are going to hide, and new image file with hidden information “new.jpg”. The “/B” stands for binary, just for your information. By adding this mark, you copy the secret data in binary mode onto the end of the new JPG image. When the picture is opened, the JPG header says the length of the data and ignores everything below (the hidden data). So, the only difference between the original and the new image files will be in the file size.

The new file with secretly attached information is ready to be sent or stored for future use. Recovering the original data is pretty easy. If inside is archive (ZIP), rename the new image from extension JPG to extension ZIP, and open with any compatible archiving program. If your file is TXT, you can rename it to text format or just open the “new.jpg” file with text editor.

For those, who like Video Tutorials, the following clips will be helpful:

HOW TO STORE/HIDE A ZIP/RAR IN AN IMAGE FILE. - More amazing videos are a click away

If you have no interest doing the procedure of the Steganography yourself, you can use free services from the following Web Site, where you get the output file automatically: http://www.steganography.computersniffer.com/

Additional Reading:

http://labnol.blogspot.com/2006/10/how-to-hide-secret-documents-or.html

http://www.techsnack.net/how-to-hide-important-information-in-an-image-file