3.7 KiB
3.7 KiB
ESPILON CTF 2026 — Official Write-ups
Official write-ups for ESPILON CTF 2026, a hardware/IoT/OT themed CTF set in the Serial Experiments Lain universe.
Challenges remain accessible at ctf.espilon.net.
Scoreboard frozen as of March 25, 2026.
Challenge Index
| # | Challenge | Category | Difficulty | Points |
|---|---|---|---|---|
| 1 | ESP Start | ESP | Easy | 50 |
| 2 | Jnouned Router | ESP | Multi | 100/200/300/400 |
| 3 | Phantom Byte | ESP | Multi | 100/200/300/500 |
| 4 | CAN Bus Implant | Hardware | Medium-Hard | 500 |
| 5 | Glitch The Wired | Hardware | Medium-Hard | 500 |
| 6 | NAVI I2C Sniff | Hardware | Medium-Hard | 500 |
| 7 | Phantom JTAG | Hardware | Medium-Hard | 500 |
| 8 | Serial Experimental 00 | Hardware | Easy | 150 |
| 9 | Signal Tap Lain | Hardware | Medium-Hard | 500 |
| 10 | Wired SPI Exfil | Hardware | Medium-Hard | 500 |
| 11 | The Wired | Intro | Medium | 400 |
| 12 | Anesthesia Gateway | IoT | Medium-Hard | 500 |
| 13 | Cr4cK W1F1 | IoT | Medium | — |
| 14 | Lain Br34kC0r3 | IoT | Medium | 500 |
| 15 | Lain Br34kC0r3 V2 | IoT | Hard | 500 |
| 16 | Lain VS Knights | IoT | Hard | — |
| 17 | Lets All Hate UART | IoT | Medium-Hard | 500 |
| 18 | Lets All Love UART | IoT | Easy | 500 |
| 19 | Nurse Call | IoT | Easy | 200 |
| 20 | Observe The Wired | IoT | Medium-Hard | — |
| 21 | Wired Airwave 013 | IoT | Medium | 500 |
| 22 | Accela Signal | Misc | Hard | 500 |
| 23 | AETHER NET | Misc | Insane | — |
| 24 | Last Train 451 | Misc | TBD | — |
| 25 | LAYER ZERO | Misc | Hard | 600 |
| 26 | Patient Portal | Misc | Medium-Hard | 500 |
| 27 | Cyberia Grid | OT | Medium-Hard | 500 |
| 28 | Operating Room | OT | Medium-Hard | 500 |
| 29 | Protocol Seven | OT | Hard | 600 |
| 30 | Schumann Resonance | OT | Medium | 400 |
| 31 | Tachibana SCADA | OT | Medium-Hard | 500 |
| 32 | GANTZ BALL CONTRACT | Web3 | Insane | 500 |
| 33 | TACHIBANA FIRMWARE REGISTRY | Web3 | Insane | 500 |
Categories
| Category | Description |
|---|---|
| ESP | ESP32 firmware — flashing, UART, WiFi, custom protocols |
| Hardware | Bus interfaces — UART, I2C, SPI, JTAG, CAN, signal decoding, voltage glitching |
| Intro | Entry point — ESPILON bot C2 infrastructure |
| IoT | IoT protocols — MQTT, CoAP, UART, SDR/FSK, WiFi cracking |
| Misc | Mixed — signal processing, web exploitation, multi-pivot |
| OT | Industrial protocols — Modbus, BACnet, OPC-UA, EtherNet/IP |
| Web3 | Ethereum — reentrancy, assembly underflow, bytecode reversal |
Author: Eun0us — ESPILON CTF 2026