Jameson Lopp, co-founder and chief security officer at self-custody platform firm Casa, raised concern about Bitcoin (CRYPTO: BTC) users repeatedly using old public addresses, a practice he viewed as a serious vulnerability in the wake of the growing quantum threat.
Users Ignoring Satoshi’s Guidelines?
Speaking to Benzinga on the sidelines of the Trezor TBD event on Oct. 21 in Prague, Czech Republic, Lopp estimated that about 4 million BTC —nearly 25% of the total supply —have already had their public addresses exposed.
"The problem here is that people just have not been following one of the simplest fundamental best practices that even Satoshi [Nakamoto] told us — never reuse a Bitcoin address," Lopp stated
For the curious, Satoshi said in one of their forum posts in 2009, "For greater privacy, it’s best to use Bitcoin addresses only once.
See Also: Bitcoin (BTC) Price Predictions: 2025, 2026, 2030
Convenience Over Security
Lopp highlighted one reason this could be happening.
"If you’re withdrawing from an exchange, you have to whitelist and go through additional security steps to tell the exchange like this is really me. And so people tend to just set that and then automatically withdraw to the same address over and over again," the Bitcoin technologist said. "And then the same thing on the deposit side."
Lopp emphasized that humans tend to prioritize convenience over everything else, including privacy and security.
"So, yeah, we’re fighting against human nature, which is never a good fight to be on," he added.
How Far Is The Quantum Threat?
Lopp estimated a “greater than 50% chance” that it will take at least another decade before a quantum computer, powerful enough to decode a Bitcoin public key to find its corresponding private key, becomes a reality.
“There are decent arguments that it may be physically impossible for us ever to achieve that level of scale with a quantum computer. And so maybe it’ll never happen. But as a technologist, I don’t like to say things are impossible,” he said.
The debate around quantum computing and its potential threat to Bitcoin has been ongoing.
Last year, Google's new "Willow" quantum computing chip sparked concerns that a powerful computer could break the encryption of the apex cryptocurrency. However, some experts said it was still "lightyears" away.
Price Action: At the time of writing, BTC was trading at $112,796, down 0.97% over the last 24 hours, according to data from Benzinga Pro.
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Photo Courtesy: Jameson Lopp
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