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🕶️ Technique Card: Discovering and Decoding Files

Unit 101 – Terminal Tigers 🐯 | Rank: Shadow Recruit

ShadowNet Agency: Recruit Training File – Classified Level 1

📁 Operation Context

In the shadows of every system, some files whisper secrets — but only to those who know how to uncover them.

This technique card gives you access to a new toolkit for reading, editing, and even decoding hidden transmissions. Master these skills and you’ll be ready to uncover and decode hidden files.

🔍 Hidden Files – Revealing the Invisible

Some files are hidden from casual users. But Shadow Recruits know better.

Use this command to see everything — even files that don’t want to be seen:

ls -a

Hidden files begin with a . (dot). If you don’t use -a, you won’t see them.

📖 Reading a File

To read the contents of a file quickly, use:

cat secret.txt

This shows the file’s content in your terminal.

Example:

cat .secretmessage.txt

✍️ Editing Files with nano

If you need to write or edit a file, use this powerful terminal editor:

nano mywork.txt

When inside nano, you can type or delete text. Press Ctrl + X to exit. If you made changes, you’ll be asked whether to save.

🧪 Creating Files (touch & echo)

You can create an empty file using:

touch newfile.txt

Or write something directly into a file like this:

echo "Hello, world!" > message.txt

This command overwrites the file with your message.

🔐 Cracking the Code – base64

You might find a message that looks like this:

U2hhZG93TmV0IHJ1bGVzIQ==

That’s Base64 — a way of hiding text. To decode it, use:

echo "U2hhZG93TmV0IHJ1bGVzIQ==" | base64 -d

This will reveal the hidden message behind the scrambled text.

Note

The | character is called a pipe and can usually be found at the bottom left corner of your keyboard

🔒 Encoding Your Own Messages

You can use base64 to encode your own messages - please remember that it is easy for an enemy to decode these so do not use this technique for top secret work.

echo "this is my message" | base64 > message.txt

🎓 Field Notes

  • Use ls -a to reveal the whispers.
  • Use cat to read them.
  • Use base64 -d to decode their secrets.
  • Use nano, touch, and echo to create your own messages.

🧪 ShadowNet Training Task

Practice your skills:

  1. Open a terminal.
  2. Use pwd to find your location.
  3. Use ls -a to look for hidden files.
  4. Use cd to enter the correct directories.
  5. Try to locate the file: .hidden-file.txt.
  6. Decode its contents.
  7. Read the secret message!
  8. Leave your own secret message for other recruits in the same directory as .hidden-file.txt | encode it with base64 and make sure it is hidden.

🐯 Only those who see the unseen can hear what files whisper. Use your tools wisely, Shadow Recruit.

⬅️ Go to Mission 002: The Whispering Files

Watch the video