> For the complete documentation index, see [llms.txt](https://alham-rizvi.gitbook.io/alhamrizvi/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://alham-rizvi.gitbook.io/alhamrizvi/cryptography/basics/03.cryptanalysis.md). # 03.Cryptanalysis ### πŸ” What is Cryptanalysis? Cryptanalysis is the process of **breaking cryptographic systems** and trying to **recover the original data (plaintext)** without knowing the key. πŸ‘‰ In simple words: **It’s the art of cracking encryption.** ### 🧠 Why is Cryptanalysis Important? * Finds weaknesses in encryption algorithms * Helps improve security systems * Used in cybersecurity, CTFs, ethical hacking ### πŸ”‘ Goal of Cryptanalysis * Recover the **plaintext** * OR find the **secret key** * OR break the encryption method ### βš”οΈ Common Types of Cryptanalysis Attacks #### 1. Ciphertext-Only Attack * Attacker only has encrypted data * Tries to guess plaintext πŸ‘‰ Hardest type #### 2. Known-Plaintext Attack * Attacker knows some plaintext + ciphertext * Uses it to find the key #### 3. Chosen-Plaintext Attack * Attacker can choose input and see output * Very powerful #### 4. Brute Force Attack * Tries all possible keys * Works if key is weak/small #### 5. Dictionary Attack * Uses common words/passwords * Faster than brute force ### πŸ§ͺ Simple Example ``` Ciphertext: KHOOR Guess: Caesar Cipher Try shifting letters back: K β†’ H H β†’ E O β†’ L O β†’ L R β†’ O Plaintext = HELLO ``` *** ### ⚠️ Real-World Use * Password cracking * Breaking weak encryption * Security testing (ethical hacking) * CTF challenges *** ### 🧠 Easy Difference * **Cryptography** β†’ Protect data πŸ” * **Cryptanalysis** β†’ Break protection πŸ”“ *** ### πŸš€ One-Line Summary **Cryptanalysis = finding ways to defeat encryption** --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://alham-rizvi.gitbook.io/alhamrizvi/cryptography/basics/03.cryptanalysis.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.