In this blog post, we will look at what steganography, a digital information protection technology, is and why it is becoming increasingly important today.
In recent years, the internet has become an indispensable part of modern life. We spend our days exploring other worlds, sending messages to each other, and communicating with the outside world through the internet. In this flood of information, people are constantly exposed to a wide variety of content, and even though they are physically distant from each other, they have become psychologically closer. With the increase in communication in the online space, the importance of personal information protection and data security is also growing day by day. In particular, the secure exchange of digital confidential information has become an important issue in modern society. Steganography is attracting attention as one solution to this problem.
Steganography is a combination of the words “stegano,” meaning “hidden,” and “graphos,” meaning “to communicate or write.” It is a deep encryption technology that hides information to be transmitted by encrypting it in image, voice, or video files that appear normal to the naked eye. The main purpose of this technology is to hide secret messages so that others cannot detect them in ordinary messages, and it is mainly used to transmit confidential information.
The first recorded use of steganography was in the 5th century BC. The Greek king Histiaeus, who was held hostage by King Darius, shaved the head of a slave and tattooed a message on it in order to deliver a secret letter to his son in Miletus. When the slave’s hair grew back and the tattoo became invisible, the king sent the slave to his adopted son. This example from ancient Greece shows how strong the human instinct to keep secrets was even then. Other examples of steganography used in the past include the following. The ancient Romans wrote letters using transparent ink made from natural ingredients such as fruit juice and milk, which could only be read when exposed to fire. This allowed them to hide the existence of secret messages. During World War II, the Germans invented “microdots,” a technique for reducing secret messages to the size of a dot. The reduced secret messages were disguised as dots in letters, such as the dot in the letter “i,” allowing large amounts of data to be transmitted without detection. The concept of steganography, which hides the very existence of secret messages, has existed since ancient times. It is known that this technology began to be applied to digital information and files around 1985, after the invention of computers and the Internet.
Steganography differs from general encryption technology, which hides the message itself, in that it hides the message in another medium to conceal its existence. Steganography technology uses insertion and modification techniques to hide messages. The insertion technique adds additional data to the front or back of a file without changing the file data, so it does not affect the original file. Modification techniques modify the least significant bit (LSB) of RGB values in image files. In other words, the pixels that make up an image file have RGB values, and these values are slightly changed to hide information. Unlike insertion techniques, modification techniques affect the original file, but even if the least significant bits are modified, it is difficult to detect with the naked eye, so this method is widely used. These techniques have been developed very sophisticatedly and have become essential tools for information security in the digital age.
Steganography can be used not only to hide confidential information of a country, but also in various other ways. For example, steganography is used to protect the copyright of content by hiding information related to the creator or copyright in multimedia data. In particular, in today’s digital age, where countless creative works are shared via the Internet, copyright infringement is becoming an increasingly serious issue. If a third party who is unaware that steganography has been used arbitrarily converts the original data, it is possible to extract the copyright-related data hidden inside and determine whether it is the original or an arbitrarily converted copy. With the increase in creative works on the Internet and the expansion of intellectual property rights over content, steganography is expected to be used more actively.
However, steganography can also be misused for criminal purposes. Steganography technology is often used by terrorist organizations to issue orders and exchange information. This technology is known to have been used by Osama bin Laden, the leader of an international terrorist organization, to send messages to his followers during the September 11, 2001 terrorist attacks. Bin Laden hid a blueprint of an airplane in a photo of the Mona Lisa and sent it to his followers via email. Steganography technology is also used to spread malicious code. It has been revealed that steganography technology has long been used not only as a simple encryption technology for secretly transmitting messages, but also for hiding malware. When a user clicks on an image, voice, or video file that contains hidden malware, the malware is installed on the user’s PC and begins additional criminal activities. These criminal applications clearly demonstrate the dangers of steganography. Attacks using steganography are almost impossible to detect with the naked eye and are very difficult to detect even with existing malware detection tools and defense software. The only way to prevent such criminal acts is to regularly update software. As such, steganography can be used for good purposes, such as transmitting confidential government information or protecting the copyright of creative works, but it can also be exploited for criminal activities.
As shown in the examples above, steganography can be used in a variety of fields. However, in order for this technology to be more widely used, the following disadvantages must not be ignored. The disadvantage of steganography is that it involves placing secret files within ordinary files, which can arouse suspicion because the file size becomes larger than the visible message. To avoid such suspicion, it is necessary to pay more attention to file size and format, and if necessary, additional encryption technology should be used in parallel. The modification technique used in the image file mentioned above is difficult to detect with the naked eye, but it can be detected by comparing pixel values. In addition, files hidden using steganography are only hidden in terms of their existence, and most of them are not encrypted, so once steganography is detected, the secret message can be revealed using a tool.
So far, we have learned about the technology of steganography. Steganography is a technology that hides secret messages in ordinary image files or video files. Steganography is invisible to the naked eye, making it difficult to even know that the message exists. Thanks to this characteristic, this technology can be used in various fields, and its importance is growing, especially in the digital age. However, in order for this technology to be applied to more fields, its shortcomings must be further improved. Therefore, if the weaknesses of steganography are addressed and the technology is not misused, we believe that it can be further developed and widely used in positive ways.
