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‎_posts/2025-12-13-guides-cyber-chef-i.md‎

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---
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title: CyberChef I
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date: 2025-12-13
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categories:
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- Guides
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- CyberChef
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tags:
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- stoutctf 2025
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- crypto
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- guides
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- challenges I created
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description: CyberChef Guide Part I
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image:
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path: /assets/img/guides/cyberchef/cyberchef-128x128.png
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alt: CyberChef logo
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post: false
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---
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> This was originally a set of walkthrough challenges I created for StoutCTF 2025. They have been re-uploaded here as guides after the fact. CyberChef VIII - CyberChef X are considered to be writeups, and are in the writeups category.
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>
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>CyberChef VIII: http://slavetomints.com/posts/stoutctf-cyber-chef-viii/
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>CyberChef IX: http://slavetomints.com/posts/stoutctf-cyber-chef-ix/
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>CyberChef X: http://slavetomints.com/posts/stoutctf-cyber-chef-x/
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{: .prompt-info }
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Can you decode this ciphertext?
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`U1RPVVRDVEZ7Zk1USldKQXFIS2NTZ0pRSlBueUIxRnJ2NGk2NGI5UFl9`
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## Walkthrough
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Welcome to the CyberChef Walkthroughs! Here we are going to go through the basics of CyberChef, with a few extra challenges at the end for you to work on.
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To start, talk about what CyberChef is (You can find it [here](https://cyberchef.io)).
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CyberChef is a security tool created by the GCHQ, who is the UK's intelligence, security and cyber agency. They describe it as:
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> CyberChef is a simple, intuitive web app for carrying out all manner of "cyber" operations within a web browser. These operations include simple encoding like XOR and Base64, more complex encryption like AES, DES and Blowfish, creating binary and hexdumps, compression and decompression of data, calculating hashes and checksums, IPv6 and X.509 parsing, changing character encodings, and much more.
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CyberChef works of off something called recipes, which are any number of basic operations built on top of each other. You can see the building blocks on the left-hand side of the application. Sometimes you only need one, sometimes you need multiple blocks to work through your text. We will be starting basic, and moving on from there.
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![the basic interface](/assets/img/guides/cyberchef/cyberchef-1-layout.png)
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So lets place our ciphertext into the input section of CyberChef. Your screen should now look like this:
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![look ma i have input](/assets/img/guides/cyberchef/cyberchef-1-input.png)
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*"Look Ma I have input!!!"*
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Okay, now, if you didnt know already, the input that we have is Base64 encoded. If you want to learn more about Base64, check out its [Wikipedia Article](https://en.wikipedia.org/wiki/Base64). In order to decode it, we can search `From Base64`, and drag it into our recipe. See how in the output, there now is our decoded string!
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![all done!](/assets/img/guides/cyberchef/cyberchef-1-decoded.png)
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Congrats on using CyberChef for the first time!
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FLAG: `STOUTCTF{fMTJWJAqHKcSgJQJPnyB1Frv4i64b9PY}`

‎_posts/2025-12-13-guides-cyber-chef-ii.md‎

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---
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title: CyberChef II
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date: 2025-12-13
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categories:
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- Guides
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- CyberChef
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tags:
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- stoutctf 2025
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- crypto
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- guides
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- challenges I created
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description: CyberChef Guide Part II
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image:
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path: /assets/img/guides/cyberchef/cyberchef-128x128.png
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alt: CyberChef logo
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post: false
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---
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> This was originally a set of walkthrough challenges I created for StoutCTF 2025. They have been re-uploaded here as guides after the fact. CyberChef VIII - CyberChef X are considered to be writeups, and are in the writeups category.
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>
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>CyberChef VIII: http://slavetomints.com/posts/stoutctf-cyber-chef-viii/
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>CyberChef IX: http://slavetomints.com/posts/stoutctf-cyber-chef-ix/
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>CyberChef X: http://slavetomints.com/posts/stoutctf-cyber-chef-x/
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{: .prompt-info }
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Can you decode this ciphertext?
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`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`
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## Walkthrough
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Welcome back to the CyberChef Walkthroughs! Here we are going to go through the basics of CyberChef, with a few extra challenges at the end for you to work on.
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This time, we are going to talk about stacking up blocks to make a full fledged recipe. Last time we learned how to use just one block, but that's pretty boring. We want to really start to push CyberChef to its limits.
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All you need to do is drag another block down onto the recipe, and voilà, you have it!
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![cyber chef](/assets/img/guides/cyberchef/cyberchef-2-multiple.png)
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*Its really that easy?*
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Now, try and figure out how many `From Base64` blocks are needed to decode this message. (Hint hint, its more than two!)
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FLAG: `STOUTCTF{rUgorocQNlGKuRxRTDAhQhzjwhTvaHDw}`

‎_posts/2025-12-13-guides-cyber-chef-iii.md‎

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---
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title: CyberChef III
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date: 2025-12-13
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categories:
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- Guides
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- CyberChef
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tags:
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- stoutctf 2025
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- crypto
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- guides
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- challenges I created
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description: CyberChef Guide Part III
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image:
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path: /assets/img/guides/cyberchef/cyberchef-128x128.png
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alt: CyberChef logo
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post: false
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---
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> This was originally a set of walkthrough challenges I created for StoutCTF 2025. They have been re-uploaded here as guides after the fact. CyberChef VIII - CyberChef X are considered to be writeups, and are in the writeups category.
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>
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>CyberChef VIII: http://slavetomints.com/posts/stoutctf-cyber-chef-viii/
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>CyberChef IX: http://slavetomints.com/posts/stoutctf-cyber-chef-ix/
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>CyberChef X: http://slavetomints.com/posts/stoutctf-cyber-chef-x/
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{: .prompt-info }
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Can you decode this ciphertext?
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`53544f55544354467b5263465a4a504a69656b34303744753071774a69323674454351747562334c657d`
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## Walkthrough
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Welcome back to the CyberChef Walkthroughs! Here we are going to go through the basics of CyberChef, with a few extra challenges at the end for you to work on.
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This time, we are going to explore how CyberChef can handle multiple types of encodings, not only Base 64. We'll do that by exploring Base 16, better known as Hexadecimal.
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This is very similar to the first walkthrough, where we are going to put our ciphertext into the input, and out block into the recipe. However, I want you to try and find the correct block now. Can you decode the hexadecimal? I guess we'll find out!
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FLAG: `STOUTCTF{RcFZJPJiek407Du0qwJi26tECQtub3Le}`

‎_posts/2025-12-13-guides-cyber-chef-iv.md‎

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---
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title: CyberChef IV
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date: 2025-12-13
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categories:
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- Guides
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- CyberChef
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tags:
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- stoutctf 2025
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- crypto
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- guides
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- challenges I created
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description: CyberChef Guide Part IV
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image:
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path: /assets/img/guides/cyberchef/cyberchef-128x128.png
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alt: CyberChef logo
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post: false
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---
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> This was originally a set of walkthrough challenges I created for StoutCTF 2025. They have been re-uploaded here as guides after the fact. CyberChef VIII - CyberChef X are considered to be writeups, and are in the writeups category.
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>
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>CyberChef VIII: http://slavetomints.com/posts/stoutctf-cyber-chef-viii/
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>CyberChef IX: http://slavetomints.com/posts/stoutctf-cyber-chef-ix/
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>CyberChef X: http://slavetomints.com/posts/stoutctf-cyber-chef-x/
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{: .prompt-info }
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Can you decode this ciphertext?
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`4e544d314e44526d4e5455314e44517a4e5451304e6a64694e47553059544d304e6a6b334d5459334e7a59334d444d784e6a6b30595459314e444d304e6a5a694e6a6b324e5452694e4463325a4451304e7a41324e7a4d794d7a41334f5455344e6a45314f544d774e5455305a44646b`
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## Walkthrough
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Welcome back to the CyberChef Walkthroughs! Here we are going to go through the basics of CyberChef, with a few extra challenges at the end for you to work on.
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This time, we are going to be super duper lazy, and solve the entire challenge using a single block!
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I know, I know, its a lot to ask, but trust me its possible. We're going to learn about the `Magic` block this time.
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The Magic block has four main components to it: Depth, Intensive Mode, Extensive Language Support, and Crib.
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### Depth
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Depth allows you to specify how "deep" or how many layers of encoding might be on the cipher text. For example, the cipher text in CyberChef II had 2 layers of encoding.
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### Intensive Mode
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Intensive mode makes the Magic block try more complex combinations than it normally would. Be careful, this can crash the application depending on the ciphertext.
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### Extensive language Support
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This is a mode you might not regularly use. This let's CyberChef know you want it to check against all languages, not just the most common ones.
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### Crib
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This tells CyberChef what the start of the plaintext is, so it can only show you ones that contain the crib in it.
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Now that you've learned all about `Magic`, you can try and solve this challenge.
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FLAG: `STOUTCTF{NJ4iqgvp1iJeCFkieKGmDpg20yXaY0UM}`

‎_posts/2025-12-13-guides-cyber-chef-v.md‎

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---
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title: CyberChef V
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date: 2025-12-13
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categories:
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- Guides
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- CyberChef
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tags:
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- stoutctf 2025
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- crypto
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- guides
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- challenges I created
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description: CyberChef Guide Part V
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image:
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path: /assets/img/guides/cyberchef/cyberchef-128x128.png
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alt: CyberChef logo
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post: false
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---
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> This was originally a set of walkthrough challenges I created for StoutCTF 2025. They have been re-uploaded here as guides after the fact. CyberChef VIII - CyberChef X are considered to be writeups, and are in the writeups category.
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>
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>CyberChef VIII: http://slavetomints.com/posts/stoutctf-cyber-chef-viii/
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>CyberChef IX: http://slavetomints.com/posts/stoutctf-cyber-chef-ix/
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>CyberChef X: http://slavetomints.com/posts/stoutctf-cyber-chef-x/
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{: .prompt-info }
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Can you decode this ciphertext?
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`**********S**********T**********O**********U**********T**********C**********T**********F**********{**********E**********4**********S**********G**********d**********t**********N**********9**********H**********t**********e**********2**********R**********E**********S**********G**********x**********h**********Y**********Y**********5**********3**********E**********V**********j**********Y**********u**********D**********l**********S**********H**********U**********}**********`
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## Walkthrough
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Welcome back to the CyberChef Walkthroughs! Here we are going to go through the basics of CyberChef, with a few extra challenges at the end for you to work on.
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This time, we are going to look into how you can use CyberChef to do simple data sanitization. This flag is covered in asterisks, and we need to remove them. Let's also try to do this with only one `Find / Replace` block.
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Now, if you simply tried to put the an asterisk into the Find field, you'd get an error. So we'd need to change it to the `Simple String` setting. And since we need to just simply remove them, we can leave the `Replace` field empty.
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So our recipe should now look like this:
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![recipe](/assets/img/guides/cyberchef/cyberchef-5-recipe.png)
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Now you should have your flag!
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FLAG: `STOUTCTF{E4SGdtN9Hte2RESGxhYY53EVjYuDlSHU}`

‎_posts/2025-12-13-guides-cyber-chef-vi.md‎

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---
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title: CyberChef VI
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date: 2025-12-13
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categories:
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- Guides
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- CyberChef
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tags:
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- stoutctf 2025
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- crypto
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- guides
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- challenges I created
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description: CyberChef Guide Part VI
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image:
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path: /assets/img/guides/cyberchef/cyberchef-128x128.png
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alt: CyberChef logo
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post: false
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---
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> This was originally a set of walkthrough challenges I created for StoutCTF 2025. They have been re-uploaded here as guides after the fact. CyberChef VIII - CyberChef X are considered to be writeups, and are in the writeups category.
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>
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>CyberChef VIII: http://slavetomints.com/posts/stoutctf-cyber-chef-viii/
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>CyberChef IX: http://slavetomints.com/posts/stoutctf-cyber-chef-ix/
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>CyberChef X: http://slavetomints.com/posts/stoutctf-cyber-chef-x/
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{: .prompt-info }
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Can you decode this ciphertext?
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`MNIONWNZ{ksZHombA4Z84sBq1dlOH3oXu7rJEYms8}`
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## Walkthrough
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Welcome back to the CyberChef Walkthroughs! Here we are going to go through the basics of CyberChef, with a few extra challenges at the end for you to work on.
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This time, we are going to look at translations and rotations. One of the easiest ways to do this is with the `ROT 13` block.
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The way that ROT works is that is shifts letters one to the side, such as that `a` becomes `b`, and so on and so forth. The Caesar Cipher works with a shift of three characters. `a` becomes `d`, `b` becomes `e`, and etc.
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If we rotate `Hello, World!` by 13 characters, `Uryyb, Jbeyq!`, and to find the shift to rotate back to the original text, we have two options.
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If we know what the original shift was, we can subtract that from 26, which is why if you shift something by 13, all out need to do is shift it by 13 again.
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The other option is to simply try all 26 shifts, which is doable, but it does take a little longer to do.
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Use the `ROT 13` block to find the amount of shift to get the flag!
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FLAG: `STOUTCTF{qyFNushG4F84yHw1jrUN3uDa7xPKEsy8}`

‎_posts/2025-12-13-guides-cyber-chef-vii.md‎

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---
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title: CyberChef VII
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date: 2025-12-13
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categories:
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- Guides
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- CyberChef
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tags:
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- stoutctf 2025
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- crypto
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- guides
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- challenges I created
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description: CyberChef Guide Part VII
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image:
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path: /assets/img/guides/cyberchef/cyberchef-128x128.png
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alt: CyberChef logo
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post: false
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---
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> This was originally a set of walkthrough challenges I created for StoutCTF 2025. They have been re-uploaded here as guides after the fact. CyberChef VIII - CyberChef X are considered to be writeups, and are in the writeups category.
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>
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>CyberChef VIII: http://slavetomints.com/posts/stoutctf-cyber-chef-viii/
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>CyberChef IX: http://slavetomints.com/posts/stoutctf-cyber-chef-ix/
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>CyberChef X: http://slavetomints.com/posts/stoutctf-cyber-chef-x/
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{: .prompt-info }
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Can you decode this ciphertext?
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`\x52\x55\x4e\x54\x55\x42\x55\x47\x7a\x33\x66\x79\x62\x64\x6b\x43\x32\x69\x74\x4a\x64\x6f\x6a\x70\x63\x4a\x44\x66\x75\x49\x4c\x56\x58\x50\x48\x40\x62\x55\x56\x38\x6c\x7c`
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## Walkthrough
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Welcome back to the CyberChef Walkthroughs! Here we are going to go through the basics of CyberChef, with a few extra challenges at the end for you to work on.
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This time, we are going to talk about our last topic, brute forcing.
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CyberChef does have limited brute force capabilities built into it. We'll be looking at `XOR Brute Force` this time.
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First things first, we need to read the ciphertext as hex, so let's first add the `From Hex` with `\x` as the delimiter. Then, we can look into breaking the XOR encryption on it.
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The nice things about XOR, is the same value you use to encrypt, is the same one you use to decrypt, so let's go through and try to use brute force to get it. Go ahead and drag the `XOR Brute Force` block into the recipe.
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You'll notice that it shows the first 100 hexadecimal keys, and it can be pretty hard to parse through that, so let's fill in the crib with the flag header `STOUTCTF{`, to see if we get a match.
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And just like that, you've learned the basics on how to do brute force wiith CyberChef. By now, you should be familiar with the basics of the program, so challenges VIII, IX, and X will be all on your own. Good luck!
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FLAG: `STOUTCTF{2gxcejB3huKenkqbKEgtHMWYQIAcTW9m}`

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