Challenge list
01. First Steps - Binary and Hexadecimal
In the security world, binary and hexadecimal are commonly used. In this challenge, convert hexadecimal to ASCII…
02. Hidden Secret - Base64 Decode
Base64 is an encoding method used to transmit binary data as text. It's not encryption, but it's often used for…
08. Network Basics - Learn Port Numbers
Networks use port numbers to identify services. For example, a web server (HTTP) usually uses port 80, and encrypted…
09. Python Automation - File Reading
In security work, programming is essential for processing large amounts of data. In this challenge, you'll use Python…
10. Security Basics - Ethics and Rules
To become a white hat hacker, knowledge of ethics and laws is just as important as technical skills. In this…
11. Decode the Caesar Cipher
The Caesar cipher is one of the oldest classical ciphers used by Julius Caesar. It encrypts by shifting alphabet…
12. Identify File Signatures
Files contain identification information called "magic bytes" at the beginning. Even if the extension is disguised,…
13. Hidden Metadata in Images
Photos and images contain metadata called EXIF. This metadata records shooting date, camera info, GPS coordinates,…
14. ROT13 Magic
ROT13 (Rotate 13) is a type of Caesar cipher that shifts the alphabet by 13 letters. Interesting feature of ROT13:…
15. Extract Strings from Binary
Binary files (executables, etc.) contain human-readable strings. Passwords, URLs, error messages, and other hints can…
AES-ECB Mode Weakness
ECB leaks repeated block patterns. This introductory task first checks the difference between encryption and encoding.…
API Requests - Find the Highest-Profit Trade
When the container starts, a stock API begins running on http://localhost:9102 (you do not need to start server.py).…
Find Attack in Apache Logs
Analyze the Apache access.log (common format) to find traces of SQL injection. Tell which attacks succeeded and which…
Bash Scripting - Power of Automation
/app/numbers.txt contains numbers from 1 to 1000, one per line. Extract all numbers that satisfy these conditions and…
Flag Hidden in Excel Macro
Analyze the macro code embedded in the Excel workbook and find the hidden authentication code (the flag). Learn how to…
Git Detective - Lost Commit
/app/repo is a Git repository. A developer accidentally deleted a commit containing important information. Use git…
JSON Master - Data Extraction
/app/users.json contains information of 100 users in JSON format. Extract users that meet these conditions: - age…
OSINT Basics - Metadata Analysis
Files recovered from a departed employee's shared drive (photos `IMG_*.jpg` and Office documents) are in…
Hidden PDF Streams
The PDF file contains compressed object streams. An internal note that is not shown on the page is hidden inside them.…
Python Practice - Bulk Base64 Stream Decoding
Every line of data.txt (about 150 lines, created at every start) is Base64. Decode line by line; when the result…
Python Practice - Conditional CSV Sales Filtering
data.txt, created at every start, is a sales CSV (transaction_id,date,product_id,amount,status,ref,notes). Several…
Python Practice - Compound JSON User Query
Examine the JSON data.txt ({"users": [...]}) created at every start. Each user has id, name, email, role, active and…
Python Practice - Target-IP Access Log Tracing
data.txt (about 1,300 lines, created at every start) is a web server access log. Extract only the requests from…
Python Automation - Bulk Base64 Decoding
Every line of data.txt (about 150 lines, created at every start) is Base64. Decode line by line; when the result…