What is Steganography? Cybersecurity Explained

Steganography is the way of presenting information within another message or an object. It's an art form of hiding secret information in plain sight.

In today's digital age, the field of cybersecurity is attracting more and more attention. Protection of information and communications are two particular areas of cybersecurity that are of high value. Some specific tools and techniques can be employed to better protect data and information from prying eyes. Steganography is one of the best-known techniques in this area. It has been hailed as the art of hiding information/data in plain sight. For centuries, steganography was used to conceal secret data within innocent-looking files, pieces of paper, or even in publications as well as artwork.

Steganography allows information to be covertly transmitted without arousing suspicion. You might be wondering – well, what exactly this technique is, who invented it, how it works, what are its application and legal aspects. In this article, we will take a deep dive into the captivating world of steganography and will try to answer all of the listed questions.

Steganography 101

Before we uncover the steganography definition, let's look at the origins of steganography first.

Origins of steganography

As you might know by simply looking at the word, the word steganography is, by origin, Greek. The ending -apathy gives it away. It's just like geography, cryptography, etc. These words all originated from the cradle of Modern Civilization – Ancient Peloponnese and the islands that surround it. In Greek, Stefanos means covered or concealed, whilst graphic means written or writing. So, as we put the two together, we get this:

Steganos (concealed) + graphia (writing) = steganography (concealed writing)

For as long as human civilization has existed, so did secrets. And when big business, politics, or war got involved, there were especially important and crucial secrets that needed to be transmitted.

Back in Ancient and Medieval times, secret messages were hidden:

In wax tablets
Using invisible inks
Tattooed on the scalps of messengers.

This image from Wikipedia shows one of the oldest technologies of steganography.

As time went by, and especially with the rise of the digital landscape, steganography has evolved to incorporate advanced algorithms and methodologies. It allows people to hide information within various digital media such as images, audio files, videos, and even text. Now certain elements can be hidden in files, and even the most complex info can be decoded in a matter of milliseconds with the right equipment.

So, to sum up, it's the technology of hiding information.

How does it work?

Basically, you have almost limitless possibilities for steganography and how you can execute it. The only condition is that both parties (the sender & the reader) have access to the same decoding knowledge or software to be able to read and interpret the message.

For now, let's focus on modern steganography and how it works.

Spread spectrum

. It's difficult to detect because the information is hidden by utilizing a few different frequency spectrums. So, the information can be hidden in formats that utilize frequencies (e.g., audio and video). By using a specific steganography decoder, you can pick up fragments of information, tie them together and get the hidden message.

Regular text steganography

. You can color code words, substitute them, use different font types and sizes, and even remove specific characters. These are just a few options for text steganography.

For example, let's say that we know these two-color codes.

If it's in green, the sentence's meaning is the opposite.
If a letter is written in purple, this means that you need to substitute it with the previous vowel in the alphabet.

So, for example, Eppli would be Apple. And the message "Enemy is unaware of our positions." This should raise grave concerns.

Video, picture steganography

. Video signals and codecs, as well as images, offer a sort of blank canvas for steganographic experts. By introducing small and even subtle changes in the video frames, such as modifying the color values of certain pixels, steganographers can successfully transfer confidential information within the video stream or picture. But there can also be malware hidden in the image, so you have to be aware of the possible problems, too (Read more).

This is a chart showing how decryption and encryption of steganographic visuals work.

Pros and applications of digital steganography

Pretty much any niche and sphere can benefit from having a secure communications channel.

Journalism. For communications with sources.
Hiding sensitive information. Usually important in business, politics, and, aforementioned, journalism. This minimizes the damage that an external attack could cause.
Digital watermarking and authenticity. The best example can be NFTs or any digital files. You can steganographically embed a digital watermark to prove authenticity or ownership. It's already being commonly used in protecting copyrights and intellectual property.

With that being said, there are much simpler methods of keeping your communications and information exchanges private. The best example is end-to-end encrypted, private messaging apps like Skyda (Read more). You can communicate with others in total privacy and have fewer concerns over data leaks or spyware. This is because any message is encrypted, and the hacker would need millions of years with the best computers (yes, millions) to decode the contents of it.

Is using steganography legal?

In general, coding and using steganography (not to be confused with stenography) is 100% legal. The contents of the hidden information are what can make it illegal. If you hide outlawed content, disclose government secrets, break NDAs, or share information that is protected, you could face legal accountability. Make sure you evaluate the risks associated with it and do not use this tech for unethical, illegal, or generally wrong purposes.

Summary

Steganography has been around for centuries. It's the tech or even artform of hiding secret information in plain sight. With the evolution of digital tech, it continues to play a crucial role in the world of cybersecurity. When used right, steganography can protect you from external attacks, leaks and keep communications private. However, as detection methods advance, the challenge lies in maintaining the delicate balance between concealing information properly and having it too easy to decode. Besides, today, there are much simpler methods to keep your communications or information sharing private.