Cyber Wave 2.0 CTF - Multi-Layer Crypto & Full Category Breakdown

1. Tournament Overview

Event: Cyber Wave 2.0 CTF
Date: 2 Mei 2026
Team: FAZer0 aishaaaursss Phya

2. Crypto: Matryoshka Key (250 pts)

Problem Description

The flag was encrypted through multiple nested cryptographic layers:

1. Fernet (AES-128-CBC + HMAC-SHA256) seeded with "clockwork-doll"
2. ChaCha20-Poly1305 authenticated stream cipher
3. AES-CBC with PBKDF2 derived keys (250,000 iterations) using combinations of system usernames (guest, backup, operator, root, admin) and numeric/symbol suffixes.

Python Unwrapping Engine

import base64
from hashlib import sha256
from Crypto.Cipher import AES, ChaCha20_Poly1305
from Crypto.Protocol.KDF import PBKDF2
from cryptography.fernet import Fernet

# Iteratively peel each cryptographic envelope
# 1. Reverse outer Fernet wrapper
# 2. Derive PBKDF2 keys across user dictionary
# 3. Decrypt inner ChaCha20-Poly1305 payload

3. OSINT Operations & Geointelligence

The OSINT track featured 8 geolocation and digital footprint tracking tasks:

• Operation Deep Dive / Final Signal: Flight telemetry tracking and ADS-B signals.
• Night Out / Kota: Landmark geolocation via What3Words tri-word address matching and Google Lens multi-spectral matching.
• Silent Peak & Sky Watcher: Mountain peak triangulation and meteorological camera cross-referencing.