Topic: how secure is double encryption of blockchain? - page 2. (Read 1993 times)

Yep. A decent cold storage wallet is as safe as it gets.

Encryption.

Backups.

Can cold wallets ever be 100% safe? They can still be stolen or damaged.

1. Malware on your PC that replaces the recipient address with its own just before it creates the signature.
2. Hacking the server, injecting something small in javascript that silently sends your private keys somewhere else (after they are decrypted by whatever security means you use client side).
3. Malware on your PC that does keylogging + man-in-middle 2FA intercepting (i.e. you think you're authorizing your login with 2FA, but actually you're authorizing the hacker who is waiting for your cellphone's result).
4. Malware on your PC that redirects your web traffic from blockchain.info to honeypotblockchainlookalike.ru.
5. Modifying your hosts file with the same effect as 4.
6. DNS hijack with the same effect as 4.

And I'm sure there are plenty of other possibilities.

Want your Bitcoins to be absolutely 100% totally safe? Use cold storage or local wallets in dedicated offline environment (e.g. Ubuntu with encrypted private keys and script to sign transactions offline).

Sounds about as secure as you're gonna get for an online wallet. This is exactly what I use for my blockchain account, except my passwords are shorter. Not sure if your passwords need to be that long, but I guess it doesn't hurt. Just make sure you don't forget them.

How/where do you store the backup of the 2FA-secret? A combination of a keylogger and a poorly secured 2FA-secret-backup could cause issues.

In any case, the length of the password doesn't really matter that much, as long as it's not extremely short. It's extremely impractical to bruteforce passwords on a web-service. Hijacked accounts come from keyloggers and other malware or reused passwords between websites, not someone bruteforcing the password.

Can someone detail me how one would even access a wallet that has 2FA + Double Encryption?

Here is the scenario

Blockchain Main Password = 30+ Characters long, Lower/Upper Case, with Special characters
- Has 2-FA with a Cell Phone
- Has Double Encryption for spending which is = 40+ Characters long, Lower/Upper Case, with Special characters (Even longer than accessing than the wallet itself)
- Lastly, the E-mail Address associated with the wallet has a different password and is also 30+ characters long.


Trying to figure out how they would be able to access that wallet. Even if they get access to the e-mail associated with the wallet at Blockchain.info, there is nothing on there.


I understand that a paper wallet is still the best and most secure wallet, but just want to see other opinions on how secure this looks based on 3 different passwords with 30+ characters.
My plan is to also diversify. Say no more than 2 BTC per wallet. Also, half stored as cold paper wallets in a safe at home or at a bank or both actually.

Thoughts?

Edit:

Also wanted to add as a security measure, all Forums and other Bank Accounts/Video Game Accounts etc. will be 30+ characters long with upper/lower and special characters (or whatever the maximum password length is) as added security. All different for each account.