Security through Obscurity

Many applications contain content which is not supposed to be publicly accessible. A properly implemented authorization model would ensure that only users with appropriate permission can access such content. If an application instead relies on the fact that the content is not visible anywhere, this is called "security through obscurity" which is a severe anti-pattern:

In security engineering, security through obscurity (or security by obscurity) is the reliance on the secrecy of the design or implementation as the main method of providing security for a system or component of a system. A system or component relying on obscurity may have theoretical or actual security vulnerabilities, but its owners or designers believe that if the flaws are not known, that will be sufficient to prevent a successful attack. Security experts have rejected this view as far back as 1851, and advise that obscurity should never be the only security mechanism.[1]

Challenges covered in this chapter

Name Description Difficulty

Blockchain Hype

Learn about the Token Sale before its official announcement.


Privacy Policy Inspection

Prove that you actually read our privacy policy.



Rat out a notorious character hiding in plain sight in the shop.


Learn about the Token Sale before its official announcement

Juice Shop does not want to miss out on the chance to gain some easy extra funding, so it prepared to launch a "Token Sale" (synonymous for "Initial Coin Offering") to sell its newly invented cryptocurrency to its customers and future investors. This challenge is about finding the prepared-but-not-yet-published page about this ICO in the application.

An initial coin offering (ICO) is a controversial means of crowdfunding centered around cryptocurrency, which can be a source of capital for startup companies. In an ICO, a quantity of the crowdfunded cryptocurrency is preallocated to investors in the form of "tokens", in exchange for legal tender or other cryptocurrencies such as bitcoin or ethereum. These tokens supposedly become functional units of currency if or when the ICO’s funding goal is met and the project launches.

ICOs provide a means by which startups avoid costs of regulatory compliance and intermediaries, such as venture capitalists, bank and stock exchanges, while increasing risk for investors. ICOs may fall outside existing regulations or may need to be regulated depending on the nature of the project, or are banned altogether in some jurisdictions, such as China and South Korea.

[…​] The term may be analogous with "token sale" or crowdsale, which refers to a method of selling participation in an economy, giving investors access to the features of a particular project starting at a later date. ICOs may sell a right of ownership or royalties to a project, in contrast to an initial public offering which sells a share in the ownership of the company itself.[2]

  • Guessing or brute forcing the URL of the token sale page is very unlikely to succeed.

  • You should closely investigate the place where all paths within the application are defined.

  • Beating the employed obfuscation mechanism manually will take some time. Maybe there is an easier way to undo it?

Prove that you actually read our privacy policy

User agreements and privacy policies are too often simply dismissed or blindly accepted. This challenge kind of forces you to reconsider that approach.

Rat out a notorious character hiding in plain sight in the shop

Steganography is the practice of concealing a file, message, image, or video within another file, message, image, or video. The word steganography combines the Greek words steganos (στεγανός), meaning "covered, concealed, or protected", and graphein (γράφειν) meaning "writing".

The first recorded use of the term was in 1499 by Johannes Trithemius in his Steganographia, a treatise on cryptography and steganography, disguised as a book on magic. Generally, the hidden messages appear to be (or to be part of) something else: images, articles, shopping lists, or some other cover text. For example, the hidden message may be in invisible ink between the visible lines of a private letter. Some implementations of steganography that lack a shared secret are forms of security through obscurity, and key-dependent steganographic schemes adhere to Kerckhoffs’s principle.

The advantage of steganography over cryptography alone is that the intended secret message does not attract attention to itself as an object of scrutiny. Plainly visible encrypted messages, no matter how unbreakable they are, arouse interest and may in themselves be incriminating in countries in which encryption is illegal.

Whereas cryptography is the practice of protecting the contents of a message alone, steganography is concerned with concealing the fact that a secret message is being sent as well as concealing the contents of the message.

Steganography includes the concealment of information within computer files. In digital steganography, electronic communications may include steganographic coding inside of a transport layer, such as a document file, image file, program or protocol. Media files are ideal for steganographic transmission because of their large size. For example, a sender might start with an innocuous image file and adjust the color of every hundredth pixel to correspond to a letter in the alphabet. The change is so subtle that someone who is not specifically looking for it is unlikely to notice the change.[3]

  • There is not the slightest chance that you can spot the hidden character with the naked eye.

  • The effective difficulty of this challenge depends a lot on what tools you pick to tackle it.

  • This challenge cannot be solved by just reading our "Lorem Ipsum"-texts carefully.