Stegsolve

From aldeid
Jump to navigation Jump to search

Description

Stegsolve is a stegano solver for challenges. It provides these main functions:

  • A quick view of different bit planes and some simple transformations.
  • Data extraction from planes. This can be row order or column order, with bits treated as a bitstream and converted into bytes.
  • Some simple checking of file formats and reporting on the filesize, additional bytes, file holes, etc. This is highly dependent upon the type of image.
  • Stereogram solver - simply change the offset until the image becomes visible.
  • Frame browser for animated images. This should also work for viewing layers in multi-layered PNG files.
  • Image combiner to combine two images in a variety of ways and browse through the different combinations.

Installation

$ wget https://github.com/eugenekolo/sec-tools/raw/master/stego/stegsolve/stegsolve/stegsolve.jar

Usage

$ java -jar stegsolve.jar

It will popup a GUI where you will be able to look for a picture to analyze.

Then press the buttons at the button of the screen to navigate through the different transformations.

Example

The below example is one of the challenges from picoCTF 2018: https://2018shell.picoctf.com/static/f05dcf83df8b8a80fff7764e0449e833/nowYouDont.png

Initial picture Flag revealed
Picoctf-2018-nowyoudont-init.png Picoctf-2018-nowyoudont-flag.png