Steghide

From Embedded Lab Vienna for IoT & Security
Jump to navigation Jump to search

Summary

Steghide is a stenography program which can hide data in different kinds of image- and audio files. This can be useful if you want to send messages hidden to a second party. For this, it is important that both parties know the passphrase with which the message is encrypted. The result does not show any obvious changes in the file because the color- respectivly sample-frequencies are not changed.[1]

Requirements

  • install steghide
  • embed file
  • cover file
  • passphrase

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

Description

Embed

To hide a message in an JPEG: in this example the message to hide is the embed file (-ef) and the cover file (-cf) is picture.jpg

Embed.jpg[2]


Extract

To extract the message.txt type following:

Extract.jpg[2]

other details

There is the possibility to define a stegofile (-sf) for the output, so you do not override the coverfile.

Stegofile.jpg[2]

To extract into a specific file, you can also enter an extract file (-xf)

Extractfile.jpg[2]

Detection

If you have the original .jpeg and the manipulated .jpeg you can compare those two with an online image comparison ([1]) Here you can upload both images and you can see where the information is embedded.

Comparison.jpg[2]

On the left side you see the original picture.jpg and on the right side the result.jpg

Result.jpg[2]

The hidden information is placed in the details of the image to prevent that it is visible in the result.jpg here highlighted in red.

Commands

steghide version 0.5.1 [1]

the first argument must be one of the following:

embed, --embed          embed data
extract, --extract      extract data
info, --info            display information about a cover- or stego-file
  info <filename>       display information about <filename>
encinfo, --encinfo      display a list of supported encryption algorithms
version, --version      display version information
license, --license      display steghide's license
help, --help            display this usage information

embedding options:

-ef, --embedfile        select file to be embedded
  -ef <filename>        embed the file <filename>
-cf, --coverfile        select cover-file
  -cf <filename>        embed into the file <filename>
-p, --passphrase        specify passphrase
  -p <passphrase>       use <passphrase> to embed data
-sf, --stegofile        select stego file
  -sf <filename>        write result to <filename> instead of cover-file
-e, --encryption        select encryption parameters
  -e <a>[<m>]|<m>[<a>]  specify an encryption algorithm and/or mode
  -e none               do not encrypt data before embedding
-z, --compress          compress data before embedding (default)
  -z <l>                 using level <l> (1 best speed...9 best compression)
-Z, --dontcompress      do not compress data before embedding
-K, --nochecksum        do not embed crc32 checksum of embedded data
-N, --dontembedname     do not embed the name of the original file
-f, --force             overwrite existing files
-q, --quiet             suppress information messages
-v, --verbose           display detailed information

extracting options:

-sf, --stegofile        select stego file
  -sf <filename>        extract data from <filename>
-p, --passphrase        specify passphrase
  -p <passphrase>       use <passphrase> to extract data
-xf, --extractfile      select file name for extracted data
  -xf <filename>        write the extracted data to <filename>
-f, --force             overwrite existing files
-q, --quiet             suppress information messages
-v, --verbose           display detailed information

options for the info command:

-p, --passphrase        specify passphrase
  -p <passphrase>       use <passphrase> to get info about embedded data


References

  1. 1.0 1.1 steghide.sourceforge.net, 2021
  2. 2.0 2.1 2.2 2.3 2.4 2.5 Oliver Dorfner, 2021