I’m sure most of my readers know how to get around encryption. You can simply use an encryption software (with GUI) and encrypt all your files. But some of you may want to hide your files inside other files (not just by saving with a . extension, which you can unhide simply by using clt+h command)

Before I explain the rest, here is a disclaimer:

This should NOT be used for doing any illegal activity and I shall NOT be responsible if you take any extreme steps!

Let’s come back to our issue – hide you files!

If you Google the term ‘steganography’, you can see some interesting links about the topic. But here I’m gonna show something quite more interesting and easy to do.

We can have a demo now:

Here I have got three files:

1. A secret video

2. A secret document

3. A picture

I’m gonna show you how to hide the files and take them with you.

First of all, we need to create a tar ball (zipped) of the files. Since I’m experimenting with the stupid vista, M$ users can also try this.

I have created a tar ball containing the secret files:

(.7z is default in my M$ since I am using the open source 7 zip   )

Popup the run command and issue ‘cmd’. Now give the following code :

(note: you need to go to the directory first)

COPY /B gnu.png + secret_files.7z picture.png 

Now, you may delete your original files.

So you have:

If you double click on the picture.png file it will show:

And nothing else. And if you look at the properties, it will only show the picture specific ones:

How to extract files?

Open the file in 7zip (note that the right click will not give you this option, and you need to do it from the extractor’s window).

Problems with this method:

There are two issues with this:

1. If the FBI finds (?) that you are carrying a simple image file of 100 MB, that may arouse suspicion.

2. If some one opens the file in an extractor, you will be in trouble!

How to rectify the problems?

There are methods!

Open the file (you new png file) in a hex editor (say notepad++ with hex plugin)

Copy the first byte codes and save them in your email. Then, edit the byte code accordingly and play with the file size. You can also change the permission and also indicate that this is not a valid compressed file, so that if some one open the file in an extractor, it will simply throws up an error

Power users can go one more step ahead by performing multi-compression and muti-encryptions using different algorithms (RSA , DES/3DES , RC4 and DSA based) and pass-codes.

Happy Hacking