Add Ledger Donjon CTF - Scissors Secret Sharing puzzle

[oritwoen]

Summary

Add the Scissors Secret Sharing challenge from Ledger Donjon CTF (2020) to boha.

Puzzle Data

Field	Value
Name	Scissors Secret Sharing
Address	1EHiMwCPzcvMdeGowsowVF2X2PgLo67Qj7
Status	Solved
Prize	100 pts (CTF)
Start Date	2020-11-24 (CTF date)
Solve Date	2020-11-24
Source	https://blog.cryptohack.org/bruteforcing-bitcoin-bip39-seeds-donjon-ctf-writeup
CTF	https://donjon.ledger.com/Capture-the-Fortress/

Solution

Mnemonic (correct order):

since desk thrive carbon zone prison leaf depart hobby practice ivory luggage

Derivation: BIP44, m/44'/0'/0'/0/0

Challenge: 12 BIP39 words were distributed to 12 employees. First 2 words (Alice: since, Bob: desk) were known in order, remaining 10 words were scrambled. Task was to find correct permutation.

Technical Notes

• Address type: P2PKH (legacy, starts with 1)
• Bruteforce space: 10! = 3,628,800 permutations
• Optimization: BIP39 4-bit checksum validation (1/16 pass rate)
• This is a CTF challenge, not a traditional bounty

Questions

1. Should CTF challenges be a separate collection (e.g., ctf/) or mixed with other puzzles?
2. Should we store the mnemonic words? (similar to how b1000 stores private keys for solved puzzles)

[oritwoen]

Adding official Ledger source: https://www.ledger.com/blog/Capture-the-Fortress