In this video, Lisa Bock explains the principles behind Steganography, or hiding something in plain sight. Explore the three basic elements of steganography, the carrier, the payload, and the hidden message. Dissect an example to better understand how image steganography is used to hide a message using subtle changes in the color of pixels.
- [Voiceover] Steganography is hiding in plain sight. Now how this works is we need a carrier, maybe an image or a music file, and then we need a payload. That could be a secret document or an Excel spreadsheet. And then using the Steganography software, that creates a hidden message. Now let's take an example of how this works using image steganography. The image on the left has a secret message embedded using steganography.
I put it on top here so you can actually see this is a secret message. Over on the right, this is a plain image. Now we see the two images side by side. On the left, you can see the image with the secret message obscured. So side by side, you see one, the image with the message, and then on the right, a plain image. They shouldn't look any different to you, and that's because the human eye can only detect so many colors. So when we're talking about each color pixel, each pixel has a red, green, and blue value.
And each red, green, and blue value is represented by eight binary bits. The low-order bits are generally used and this doesn't change the color value significantly. So you can see the difference between 229 and 228 when those last two bits are used in steganography. On this slide, I've blown up two single pixels. And here we see the red, green, and blue values on the left and the right hand side.
On the left, we see 229, 84, and 147. On the right, we see 228, 84, and 144. To the eye, you really can't see that subtle difference. And that's because we can only see a certain range of color values. And that's how we can use pictures with steganography.
These tutorials, along with the other courses featured in the Ethical Hacking series, will prepare students to pass the Certified Ethical Hacker exam and start a career in this in-demand field. Find out more about the exam at https://www.eccouncil.org/programs/certified-ethical-hacker-ceh/.
- Acquiring passwords
- Generating rainbow tables
- Understanding where passwords are stored
- Defending against privilege escalation
- Understanding spyware
- Protecting against keylogging
- Detecting steganography
- How hackers cover their tracks