Wouldn't it be about time they make this open source? What if someone still wants to recover their coins years or even decades from now?
If it's just the client-side of their legacy wallet, they have the source code for that,
here:
github.com/blockchain/unused-My-WalletIt comes with the v2 wordlist and the rare v3 algorithm with the code on how to decode/encode the words.
check this file, mnemonic.js:
github.com/blockchain/unused-My-Wallet/blob/master/mnemonic.jsIt has an updated version in their legacy pages of their v4 front-end repository:
github.com/blockchain/blockchain-wallet-v4-frontend/blob/development/legacy-pages/js/mnemonic/mnemonic.jsI just checked my 2015 Blockchain wallet backup: it has 24 words, and includes words like "norsk" and "hoffmeister". I'm pretty sure the wallet is empty, but I'd have no idea how to recover this wallet.
Those are in their short-lived v3 mnemonic:
github.com/blockchain/unused-My-Wallet/blob/master/mnemonic_words_v3.htmlIf the word list has been posted in public somewhere, it should not be too difficult for someone to make a "blockchain to bip39 translator" that just maps each blockchain.com word to the bip39 word for that same position.
The problem with this is the binary seed isn't based from the BIP39 word's position in the wordlist.
So you can't just map their positions and replace the words of the same positions.
The same reason why you can't just translate a BIP39 seed phrase to another language by mapping the words' positions.
The binary seed where the master private key is generated from is derived from the words themselves so changing any character will produce a different wallet.
As for legacy Blockchain, their legacy mnemonic isn't for deriving the wallet itself, it's just an encoded backup of the user's password.
OP made this confusing since he said it's legacy from 2013 yet claimed that it consist of BIP39 words.