Hide Files in Images in Linux - Steganography Guide
Concealing Files Within Images on Linux Systems
If your Linux PC is accessed by multiple users, safeguarding sensitive files becomes crucial. While hiding files is a standard practice, those familiar with revealing hidden files can easily circumvent this method. A more discreet approach involves compressing your files and embedding them within an image.
Preparation and Compression
Begin by creating a directory that houses both an image file – such as a .png or .jpg – and the file or folder you intend to conceal. For this example, we will hide a directory named secret_files within an image called htg-site.png. Utilize the cd command to navigate to this directory.
cd files_to_hide/
Next, we will compress the directory we wish to hide. This is achieved using the following command:
zip -r secret.zip secret_files/
The -r flag ensures that all subdirectories within secret_files are included in the compressed archive. The resulting compressed file will be named secret.zip.
Confirm the creation of the compressed file by typing ls and pressing Enter. You should now see secret.zip listed among the files.
Embedding the Archive into the Image
Now, the compressed file will be combined with the image file, creating a new image that contains the hidden data. This is accomplished using the cat command.
cat htg-site.png secret.zip > secret.png
Ensure the original image file is listed first, followed by the compressed file. The redirection operator (>) directs the combined output into a new image file named secret.png.
After executing the command, verify the creation of the new image file, secret.png, using the ls command. This image now contains your hidden archive.
Cleanup and Extraction
Once the new image is created, the original compressed file and the source folder can be safely deleted using the rm command.
rm secret.zip
rm -r secret_files
To retrieve the hidden file or folder, navigate to the directory containing the secret.png image. Then, extract the contents using the following command:
unzip secret.png
Remember to replace secret.png with the actual name of your image file.
The secret_files directory will be restored, and its contents can be accessed by navigating into it (cd secret_files/) and listing the files (ls).
Security Considerations
It’s important to note that this method provides a degree of obfuscation, rather than robust security. It makes files less readily visible to casual observers. For enhanced protection, consider encrypting your zip files before embedding them within images.
Similar techniques can also be employed to hide compressed files within images on Windows operating systems.
Related: How to Hide Zip Files Inside a Picture Without any Extra Software in Windows