Ledger Donjon CTF

The puzzle

Scissors Secret Sharing was a 100-point challenge in Ledger Donjon's Capture the Fortress CTF. Twelve employees each held one word of a BIP39 mnemonic. The first two words kept their positions, the other ten got mixed up. Despite the name, these aren't Shamir shares.

Ledger's announcement dates the competition from October 28 to November 18, 2020. The record uses that opening day. November 24 is the publication date of joachim's CryptoHack write-up, not the start or a known solve date.

What the record carries

The write-up publishes the ordered phrase and the BIP44 path. verify() derives the challenge address from those exact values. No search is needed, the answer is already public.

export const ledgerDonjonPuzzleScissorsSecretSharing = bitcoinPuzzle({
  id: "ledger_donjon/scissors_secret_sharing",
  address: p2pkh("1EHiMwCPzcvMdeGowsowVF2X2PgLo67Qj7"),
  sourceUrl: "https://blog.cryptohack.org/bruteforcing-bitcoin-bip39-seeds-donjon-ctf-writeup",
  startedAt: "2020-10-28",
  status: Status.Solved,
  key: seed(
    "since desk thrive carbon zone prison leaf depart hobby practice ivory luggage",
    "m/44'/0'/0'/0/0",
  ),
  solver: party("joachim"),
});

Status

Solved, with joachim credited for the published solution, not asserted to be the first solver. The record leaves solvedAt and transactions absent because the write-up doesn't establish either. Its 100 points were a CTF score, so prize stays absent too. Treating points as BTC would quietly corrupt the dataset's totals.

Every puzzle