A group called the "Large Bitcoin Collider" claims it can smash open bitcoin wallets by using a so-called brute force attack, which directs mass amounts of computer power at individual wallets in order to guess their private keys.
The project, which has been underway for months, relies on a distributed network of computers (similar to bitcoin itself), and invites anyone to participate—those who do could potentially share in the proceeds of the wallets cracked open.
A "trophy list" on the home page of Collider (an apparent reference to the Hadron Collider) suggests the group has successfully opened over a dozen wallets, though only three had any bitcoin in them. It's unclear if the group is motivated by financial gain or the cryptographic challenge of smashing wallets—the answer is probably both based on the site's webpage and outside observers.
A Q&A list on the Collider's website says robbing even a tiny amount from non-profit group like the Internet archive "would make you an unconditional jerk." But it also suggests other wallets are fair game, and that proceeds would be divvied up among the Collider participants.
Meanwhile, others think the wallet-smashing endeavor is a fool's errand, according to Motherboard, which first reported on the Large Bitcoin Collider. In this view, the project is too hard and the rewards too low and infrequent (as this Reddit commenter explains) to pay off.
But some speculate the goal of the project is not to rob a whole lot of wallets, but instead to strike a mother lode from a long-lost wallet from bitcoin's early days:
"About 10% of Bitcoins were created early, before 2012, and have never been traded. If somebody ever finds the key of the early lost Bitcoins, they'll have a huge payoff, over a billion dollars. Speculation is that either "Satoshi Nakamoto", whoever he is, is holding onto them for a big payoff, or somebody lost the private key for all those early Bitcoins. As the years go on, the second explanation seems more likely," said the top comment on the site Hacker News.
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As for the process of cracking open wallets, it involves the laborious task of creating private keys—which are dozens of characters in length—and trying them against existing bitcoin addresses. The Collider has so far created and checked 3,000 trillion private keys, a researcher told Motherboard.
As for the legality of all this, it's unclear. On one hand, the law is pretty clear that you are not supposed to join a conspiracy in order to rob people. But on the other hand, as the group's website points out, "It is not illegal to search for colliding private keys."
For bitcoin owners, the risk of the Large Bitcoin Collider performing a stick-up on your private wallet is pretty tiny for now. But if the process also results in someone creating a collision for bitcoin's general hashing algorithm—as happened with the longtime crypographic standard SHA-1 (cracked by Google this year)—that would spell a lot more trouble, though as one reader points out, bitcoin's encryption algorithm can be upgraded.