With the sheer number of Bitcoin wallets in existence, somebody is bound to try and hack a few of them sooner or later. Brian Flayer, a tool designed to crack Bitcoin wallet addresses – particularly brainwallets – has been undergoing some improvements. With several hundred trillion private keys being tested so far, it looks like cracking brainwallets has become a lot easier as of late.

Brainwallets Were Never Safe To Begin With

Using a brainwallet has one advantage and quite a few disadvantages. The upside is how there is no software to trust when it comes to generating mnemonic recovery seeds for addresses. Users do so from memory, by using long strings or sentences that are not overly complicated to remember. This is also the fatal weakness of brainwallets, as humans tend to get sloppy when it comes to passwords, passphrases, and security.

Thankfully, the number of Bitcoin brainwallets is relatively small compared to the overall numbers. But that is not keeping researchers from trying to crack these wallets. Brainflayer is a tool often used for this type of purpose, and the tool has undergone several upgrades so far. With a 215% speed increase over the past year, the tool is hammering away at testing private keys.

But as researchers continued to experiment with Bitcoin brainwallet cracking, they noticed something interesting. Several addresses related to one particular transaction seem to have private keys increasing with each output. While it is unclear whether or not this is a deliberate attempt to see how long it would take to hack the wallet, it is an intriguing development for sure.

Trying to crack a brainwallet requires computational power and either software or a script to automate the process. A lot of people will have a go at this procedure and give up relatively quickly, depending on their success rate. Moreover, not everyone has powerful hardware at their disposal to try and crack a private key, which has always been a time-consuming process.

To put this into perspective, the higher outputs on that particular transaction will require more “guesses” per second. Output 50 requires 28 million guesses per second. Brainflayer can, right now and depending on the hardware used, complete roughly 1.5 million guesses per second. A total of 563 trillion private keys had to be tested, which required roughly 5,555 hours – or 231.48 days – of trying at maximum capacity. Less powerful computers will spend a lot more time on this process.

All of this goes to show that cracking Bitcoin brainwallets is certainly possible. The easy targets have already been emptied, though. More “advanced” and complex private keys will require a lot of time, computational power, and luck. In fact, cracking a private key for any Bitcoin address has less than a 1% chance right now. Nothing to worry about, but certainly food for thought.

Source: Rya

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