Bitcoin Forum

I am curious if private keys are vulnerable to the computational power of miners.

Can a miner or a group of miners use their huge computational power to access private keys for any public address, or the computational power is too small for that.

No. The main problem is not about their lack of computational power. Miners uses ASIC which are designed to only mine Bitcoin (ie. Only do double hashing of block headers to produce SHA256 hashes). This means that those ASICs can never ever be used to generate addresses.

That aside, even if you convert the hashing power directly to the number of keys per second, you would still need a astoundingly huge amount of time before you hit the jackpot. The probability is so small, it might be more worthwhile to just buy a huge bunch of lottery tickets and its more likely for you to hit every single one of them than to be able to bruteforce addresses that are securely generated.

There are 2 threads to read about this:
https://bitcointalk.org/index.php?topic=5147514
https://bitcointalk.org/index.php?topic=5216788


This could make you understand that there are so many possible private keys they just cannot "hack" / brute force a private key. The energy of our sun would not be enough for the effort.

An example Bitcoin private key
L1VmqTKdwzM361jkFVAT5Dd2b3APSQEW6bHs8TG2XCrGj2qVRSBb

Merkle Trees - Once hashed it will look like this:
2d94683fa2f8aaae4a6f377d93b875f680adf96b9c3e9577554b742f412fa9ad

Proof of Work
The Bitcoin protocol sets a target value for a block header’s hash. The output must be less than the specified number. Another way of saying this is that the hash of the block header must start with a certain number of zeros. For example a valid hash may look like this:
000000000000002e9067f1cf7252333f7aeb619c89d220985a70ac0e015248e0

In Bitcoin, a private key is a 256-bit number, which can be represented one of several ways. Here is a private key in hexadecimal - 256 bits in hexadecimal is 32 bytes, or 64 characters in the range 0-9 or A-F.

Thank you, now I get it, what miners do, is encrypting transaction data, and decryption of a hash is much harder work, numerous times harder, 1,000,000 and more.

I started understanding much better the function of miners by reading this article https://chrispacia.wordpress.com/2013/09/02/bitcoin-mining-explained-like-youre-five-part-2-mechanics/

That's in compressed Wallet Import Format, but that particular private key is invalid.

I think you are confused here. Private keys undergo ECDSA to give a public key, but they aren't hashed, and they certainly aren't hashed to Merkle Trees.

It's not "numerous times harder", it's impossible. Hashing is not the same as encryption. You can't "decrypt" a hash. Nor can you reverse it. It is a one way process.

Miners not, but people in front of super computers yes.
There is project somewhere, that people trying to find used already addresses by finding them with brute computing power.
They found around 4-6 already. Is this something to worry about? Not sure. Probably not because there are many theories why they found 4-6 already.

Are you sure? There is a difference between how set of public/private keys are used and how block is mined.

Keys are generated through Elliptic Curve Cryptography. It is one way tap door. We don't use any hashing or encryption technique in ECDSA. Instead we use special generator point G whose value is taken from secp256k1 curve. It is next to impossible to find private key from public key.

However, it is somewhat possible from signatures. When signing a message, ecdsa curve takes another parameter i.e. random number. This number is used to generate R parameter of signature. If same number is used to sign more than one message then it is possible to crack private key from R and S values of signature. Similar incident happened with Sony when the company signed their play station with ecdsa key pair but uses same value for R parameter than random number. But there is no back door for brute forcing directly on public key.

I guess you are talking about Large Bitcoin Collider (Collision Finders Pool) (https://bitcointalk.org/index.php?topic=1573035.0).
If so, I recommend you to read this article (https://cryptoiq.co/the-large-bitcoin-btc-collider-a-pool-of-computers-attempting-to-brute-force-bitcoin-btc-private-keys-calculates-300-500-million-keys-per-second-and-36080-trillion-private-keys-generated-so-far/).


Not only this project is not a worry, but also it proves security of private keys.

The answer is no. Miner rigs can't get your private key. Miner rig is use to solve hash. Private key is not encrypted that you can decrypt by brute force. The people behind the computer can get your private keys like through a phishing site, malwares and viruses that they can steal your private key and also damage your computer files.

Can we get a source on this? As far as I know, these have only ever happened to poorly generated private keys. If you're using a proper wallet to generate your keys, you should be practically immune to any brute force attack, at least with current technology.

Here's (https://crypto.stackexchange.com/questions/52571/computational-requirements-for-breaking-sha-256) a discussion on what it would take to break the SHA256 encryption.

(If you're talking about the Large Bitcoin Collider project, it's a sham (https://bitcointalk.org/index.php?topic=5185726.0).)

They dont have the power to get your private keys, the only way others can get your keys is when they hack your pc, or they stole your hard drive, which is impossible

you mean "elliptic curve point multiplication".
ECDSA is Elliptic Curve Digital Signature Algorithm, that is used to create the signatures (r and s pair) through a different equation.

I'm not sure what are you referring to with the 'impossible' part but stealing others' private key through phishing, remote execution, clipboard hack, keylogging etc is definitely possible. It's already happening here and there.

As i read and i read a lot no the private keys are not vulnerable and even quantum computers will not can bruteforce bitcoin private keys.

Yes, first I was confused, but I realized, that hashed input on merkle tree is based on transaction data which is encrypted.

And yes, there is no data to decrypt the private key, miners don't have any input information to decrypt private keys, so there is no way to make some computations to find out the private key, it will be just a random guess, which is nearly to impossible to find a correct key.

I was confused, because miners do some computations or a lot of guesses per second to find a hash. Since miners try to find a random hash for pow, it will be much harder to find a specific one in case with private keys.