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HIDDEN MESSAGES


Here is a nice one for the secretive ones amongst you: How to hide a text file in a .jpeg picture. The result is you see a picture and nothing tells you there is a message hidden inside of it.
The technique is called "Steganography", there are a few programs you can use but we will only show the most simple one here.

First you need to download "outguess-0.2.tar.gz". Get it at http://www.outguess.org/
After you cd to the directory you downloaded it to, you do:
 
CODE
$ su
< password >
# tar -zxvf outguess-0.2.tar.gz
# cd outguess
# ./configure && make

Then to have a link to the executable in your path: ( adapt the first part of the command to your situation )

CODE
# ln -s /home/bruno/Downloads/outguess/outguess /usr/bin/outguess


Good. Now you are fully set up. Here is an example:

user posted image

Rightclick the image and save it to your /home, after that give the next command:

CODE
$ outguess -r  output.jpg  file.txt

and you will find all my passwords in a file.txt that will be created in your /home
Is that a nice trick or not ?

Now here is how you do it: you need a text file ( in this example we call it "file.txt" ) and a picture ( we call it "file.jpg" ) after that you issue the command:

CODE
$ outguess -d  file.txt  file.jpg  output.jpg

This will make the file "output.jpg"

Unpacking is just as simple as wrapping:

CODE
$ outguess -r  output.jpg  file.txt


Now, if you really want to be sure your data is safe you can password-protect the "output.jpg" too:

CODE
$ outguess -k "password" -d  file.txt  file.jpg  output.jpg

and unwrap:

CODE
$ outguess -k "password" -r  output.jpg  file.txt

( Note: extracing works without the password too, but you get an empty text file )

That is all there is to it.
More options are in the man-page: Here


So, I told you there are other programs too: "Steghide" is such a one and available in the Mandrake contrib sources. You can read more about it ( and Outguess too ) here:
http://distrowatch.com/weekly.php?issue=20040809#feedback
But beware, there is a typo in the command they give to wrap the steghide file. This is the correct one:
# steghide embed -ef file.txt -cf file.jpg -sf output.jpg
NOTE: ( -ef . . not -pf like they say in the Distrowatch article )

Have FUN


Bruno


-- Sep 29 2004 ( Revised Dec 15 2005 ) --


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