How to use the Vault Decryptor with the MetaMask Vault Data

If you didn't back up your 12 English words seed phrase in paper, along with any manually imported private key or JSON file, you may still be able to regain access to your wallet funds by extracting the Vault Data that is stored by the browser in your computer.

You can read how to copy your Vault Data from Chrome and Brave browsers here. If you are using Firefox or any other browser, steps might be different depending on how every browser stores the extension's data locally

In Chrome based browsers (Chrome, Chrome Canary, Brave) you can also use the Web Inspector's Console tab to type this command, which will show you the {"data":"gewun.......opQ==","iv":"JfVS.....==","salt":"jx4......FI="} part of the Vault directly.

chrome.storage.local.get('data', result => {
 var vault = result.data.KeyringController.vault
 console.log(vault)
})

Once you have the vault data (which comes JSON formatted) you can proceed to the Vault Decryptor that you can find in the link below and also see the code at GitHub.

https://metamask.github.io/vault-decryptor/ 

In the Vault Decryptor page you'll paste the {"data":"gewun.......opQ==","iv":"JfVS.....==","salt":"jx4......FI="} part of the vault data and the password you set for your wallet in the MetaMask extension. If successful, you'll see the result below the Decrypt button showing the "mnemonic" 12 English words seed phrase, along with any other imported "Simple Key Pair" (private key).

You can now use the seed phrase (and private keys) to restore your MetaMask wallet. 

We urge you strongly to make sure that you always backup your seed phrase, and any manually imported private keys, so this never happens again.