We have written few articles about the same topics but the way of using is different, how to hide files and folders in Linux & how to protect files and folders with password to safe the personal documents from others. It help us to send the secret information over the Internet like mail.
Today we are going to discuss the same topic once again but the method is completely different. I will show you, how to hide sensitive data inside image and audio files using steghide utility.
Steghide is a steganography program that allows you to hide confidential files inside an image or audio file with a passphrase. Supports BMP and JPEG image formats, AU and WAV audio formats. By default it uses Rijndael algorithm to encrypt the file and the key size is 128 bits. If you want to use any-other supported algorithm to encrypt files, use steghide --encinfo
command to bring the list.
Suggested Read : Gnome Encfs Manager – An Ease way to Create a Encrypted Directory in Linux
Suggested Read : SiriKali – GUI Front End To Manage ecryptfs, cryfs, gocryptfs, securefs, and encfs Encrypted Folders
Suggested Read : GnuPG – An Easy Way To Encrypt/Decrypt Files From Command Line in Linux
Suggested Read : Cryptkeeper – An Easy Way To Encrypt And Decrypt Folder or Directory In Linux
Steghide Features:
- Compression of embedded data
- Encryption of embedded data
- Embedding of a checksum to verify the integrity of the extraced data
- Support for JPEG, BMP, WAV and AU files
How to install Steghide in Debian systems ?
Debian systems had the steghide package in official repository, so we can easily install through Apt Package Manager or Apt-Get Package Manager.
$ sudo apt-get install steghide
For Arch Linux users, use Pacman Package Manager to install Steghide.
$ sudo pacman -S steghide
Manual method to install Steghide in Linux
Follow the below instruction for manual method to install steghide, if the distribution doesn’t have the package.
libmhash libmcrypt libjpeg zlib $ wget http://prdownloads.sourceforge.net/steghide/steghide-0.5.1.tar.gz?download $ tar -xzvf steghide-0.5.1.tar.gz $ cd steghide $ ./configure $ make $ make check $ sudo make install
How to hide a file inside image ?
Steghide doesn’t have the GUI, so run the following command on terminal to embed the file inside the image. In the following example, we are going to hide taskwarrior
text file into Linux_logo.jpg
image.
$ steghide embed -cf Linux_logo.jpg -ef taskwarrior Enter passphrase: Re-Enter passphrase: embedding "taskwarrior" in "Linux_logo.jpg"... done
Above command will embed the file taskwarrior in the cover file Linux_logo.jpg
How to Unhide/Extract a file ?
Run the following command in terminal and provide the correct passphrase to Unhide/Extract a taskwarrior file from the stego file Linux_logo.jpg, which will automatically save in the current directory.
$ steghide extract -sf Linux_logo.jpg Enter passphrase: wrote extracted data to "taskwarrior".
How to hide a file inside audio file ?
Use the same format and change the stego file type to audio instead of image file. See the following example.
$ steghide embed -cf test.wav -ef secret.odt Enter passphrase: Re-Enter passphrase: embedding "secret.odt" in "test.wav"... done
Above command will embed the file secret.odt in the cover file test.wav
How to Unhide/Extract the file ?
Run the following command in terminal and provide the correct passphrase to Unhide/Extract a secret.odt file from the stego file test.wav, which will automatically save in the current directory.
$ steghide extract -sf test.wav Enter passphrase: wrote extracted data to "secret.odt".
How to view file information before extracting ?
If you want to get some information about the file before extracting it, use the following info option with steghide command.
$ steghide info Linux_logo.jpg "Linux_logo.jpg": format: jpeg capacity: 2.0 KB Try to get information about embedded data ? (y/n) y Enter passphrase: embedded file "taskwarrior": size: 3.3 KB encrypted: rijndael-128, cbc compressed: yes
This will printing some general information about the stego file like format & capacity. Hit y
to extract the embedded data by providing passphrase.
steghide –encinfo
Displays the list of supported encryption algorithms and modes that can be used.
$ steghide --encinfo encryption algorithms: : ... cast-128: cbc cfb ctr ecb ncfb nofb ofb gost: cbc cfb ctr ecb ncfb nofb ofb rijndael-128: cbc cfb ctr ecb ncfb nofb ofb twofish: cbc cfb ctr ecb ncfb nofb ofb arcfour: stream cast-256: cbc cfb ctr ecb ncfb nofb ofb loki97: cbc cfb ctr ecb ncfb nofb ofb rijndael-192: cbc cfb ctr ecb ncfb nofb ofb saferplus: cbc cfb ctr ecb ncfb nofb ofb wake: stream des: cbc cfb ctr ecb ncfb nofb ofb rijndael-256: cbc cfb ctr ecb ncfb nofb ofb serpent: cbc cfb ctr ecb ncfb nofb ofb xtea: cbc cfb ctr ecb ncfb nofb ofb blowfish: cbc cfb ctr ecb ncfb nofb ofb enigma: stream rc2: cbc cfb ctr ecb ncfb nofb ofb tripledes: cbc cfb ctr ecb ncfb nofb ofb
Wanna know more about Steghide
If you want to know more options which is available for steghide, simply navigate to man page.
# steghide --help or # man steghide