challenges-codex

A curated, beginner‑friendly set of CRL challenges organized by category. Each challenge includes a clear write‑up and step‑by‑step solution guidance.

Categories

Web

• edu-web-01: View‑source basics (flag hidden in HTML).
• edu-web-02: Cookie inspection (flag set as a cookie).

Steganography

• edu-stego-01: Hidden strings inside an image file.

Mobile

• edu-mobile-01: APK resource inspection.

Cloud / DevOps

• edu-cloud-01: Decode a Kubernetes secret.

Hardware / IoT

• edu-iot-01: Extract strings from firmware.

Blockchain

• edu-blockchain-01: Decode a transaction memo.

Network

• edu-network-01: Find a flag inside a small PCAP.

Programming

• edu-prog-01: Simple numeric filtering and sum.

Blue-Team / DFIR

• edu-dfir-01: Identify top attacker IP from logs.

Crypto

• edu-crypto-01: Caesar cipher decode.
• edu-crypto-02: Single‑byte XOR decode.

Forensics

• edu-forensics-01: Log triage + base64 decode.
• edu-forensics-02: Extract strings from an image.

Reverse Engineering

• edu-reverse-01: Use strings to recover a flag from a binary.

Pwn

• edu-pwn-01: Classic buffer overflow to call win().

OSINT

• edu-osint-01: Find a clue in a profile dump and decode it.

Misc

• edu-misc-01: Acrostic puzzle (first letters form the flag text).

How This Repo Is Used

These challenges are consumed by the main deployment repo:

• Main repo: bv21-deployment-cyber-range
• Blueprint: crl/blueprints/generated/codex-edu.yml
• Stored event: crl/stored-events/generated/codex-edu.yml

The main repo spins up CTFd and publishes these challenges into an event.

Credits

Thanks to KAUOTIC for the Cyber Range Lite ecosystem and inspiration.