The phrase "extract hash from walletdat top" refers to the leading techniques used to pull the cryptographic hash (typically a key derivation function output like SHA-256 or scrypt) from the wallet file. This hash is the gateway to the password; once extracted, it can be fed into password-cracking tools like John the Ripper or Hashcat.
: It is highly reliable for older Bitcoin Core wallets but may struggle with newer "descriptor" wallets or files with specific database corruptions. extract hash from walletdat top