Hide confidential files in an image without software

hide a rar in an image with ms dos
hide a rar in an image with ms dos

Last updated: February 18, 2023

Whether you're at the office or at home, you're likely to share your computer with other people. However, without taking proper precautions, your personal files can be easily accessible to anyone using your computer.

If you want to protect some important files from the curiosity of others, there is a simple and effective solution: steganography. This method allows you to hide files and folders of any format (mp3, txt, avi, etc.) in an image (jpg, png, bmp, etc.) without using third-party software.

In the next sections, we will show you how to embed files into an image using the "Copy" command of Windows. We will also tell you how to extract the image files.

Follow the steps in this article to protect your personal files effectively and discreetly.

What is Steganography?

Steganography is a technique that allows information to be hidden in a seemingly innocuous medium. Unlike encryption, which makes information unreadable using an encoding algorithm, steganography conceals information in a medium that appears to hide nothing other than what is visible to the naked eye.

This technique is used to transmit confidential messages discreetly, without arousing the suspicions of those who receive them. Indeed, the information hidden in the medium can be of different types: text, images, audio files, etc.

In short, steganography is a computer security method that allows concealing confidential information.

How to hide a file in an image?

To hide a file in an image, you can follow these steps:

  • First, select a suitable image to serve as camouflage.
  • Next, create an archive containing the files you want to hide.
  • Open a command prompt or terminal and move to the folder where the image and archive are located.
  • Enter the following command in the Command Prompt window:
    copy /B The_Simpsons.jpg+My_projects.zip Top_secret.jpg
  • Make sure to replace "The_Simpsons.jpg" with the name of your image, "Mes_projets.zip" with the name of your archive and "Top_secret.jpg" with the name of the final image which will contain the hidden ZIP file. You can choose the name of the final image according to your preferences.
  • Press “Enter” to execute the command. The archive will then be merged with the image, creating a new image that contains the hidden file.

It is possible to delete the other files and only keep this new image named “top_secret.jpg”.

To access the archive hidden in the image, there are two methods:

  • The first is to open WinRAR, then browse the hard drive for the new image, then extract the files it contains.
  • The second method is to change the file extension from .jpg to .zip and then validate. You will then be able to find the ZIP file containing all your files.

Conclusion

Steganography is a data hiding technique that can be used to hide files in images. Indeed, this technique can be useful in many situations, in particular to protect the confidentiality of certain sensitive information.

In summary, steganography is a valuable technique for protecting data privacy, but its use must be done responsibly and ethically.