A man who had R6.5 million in Bitcoin locked in a wallet for 11 years used Anthropic’s Claude AI to recover the encrypted password, allowing him to regain access.

He posted the story to his X account on Wednesday and linked his Bitcoin wallet transaction history, which showed that 5 BTC remained untouched since it was placed into the wallet on 1 April 2015.

The transaction history showed that he began withdrawing BTC from the wallet on 13 May 2026, coinciding with his claims on social media.

At the time he made the first transaction, the 5 BTC in the wallet had a value of R6.55 million or $399,404. He had since withdrawn the entire amount of cryptocurrency.

In 2023, the user @cprkrn posted a link to his cryptocurrency wallet showing that it contained 5 BTC, with a value in US dollars.

“My wallet with my locked BTC from 9 years ago,” he said in 2023. On 13 May, he quoted the older post, declaring that he used Claude to “crack” it and retrieve the lost, encrypted password.

“I tried like 7 trillion passwords,” he said in a follow-up post. “Found this old [mnemonic] a few weeks ago that ended up being the old password before I changed it.”

He said that Claude managed to crack an obvious opening, but it would have been unlikely for him to do so on his own.

According to his chat history with Claude, cprkrn also tried to brute-force his way into his wallet and had the AI run Hashcat on it, attempting 3.4 trillion password combinations without success.

He also tried a BTCrecover brute-force attack on his own wallet through Claude, unsuccessfully attempting 34 billion passwords at 300,000 per second.

His last-ditch effort, he said, was dumping his entire college computer into Claude. The generative AI found an “old wallet file with the [mnemonic] successfully decrypted.”

“Locked out 11+ years because I got stoned and changed the password,” he said. The lost password ended up being “lol420fuckthePOLICE!*:).”

In his original post, he thanked Anthropic and its CEO, Dario Amodei, for launching Claude, and vowed to name his child after the AI executive.

Generative AI accelerating coding capabilities

@cprkrn’s Bitcoin wallet transactions, with the latest transactions highlighted between 2015 and 2026.
The user was essentially running a cyberattack on his own Bitcoin wallet to recover the locked cryptocurrency.

While an external threat actor would not have been able to gain access to the wallet through Claude, the fact that cprkrn kept the files on his old computer meant that Claude could decrypt the password.

The story is an example of the advancing power of generative AI in the coding and development space, with Anthropic a leader in this field.

However, there have been other examples of AI being used to find zero-day exploits in company systems that would have been extremely difficult for humans to find on their own.

Earlier in May, researchers from security firm Theori used their “AI hacker” called Xint Code to help them uncover a high-severity Linux kernel vulnerability.

Researcher Taeyang Lee believed there was an underexplored bug class in a specific area of Linux’s crypto system, which he tasked Xint Code to look into.

“From there, Xint Code scaled the audit across the entire crypto subsystem in roughly an hour. Copy Fail was the highest-severity finding in the run,” Theori stated.

Concerns are growing that these same AI capabilities can be exploited by cybercriminals to run more severe, faster breaches of global company systems.

Bijan Sanii, CEO of Canadian fraud detection provider Inetco, told MyBroadband that South African banks and financial institutions should be aware of the implications.

Inetco provides fraud protection for financial institutions worldwide, including Standard Bank and African Bank locally.

“For South African institutions, the issue is that AI is accelerating the discovery, testing and potential weaponisation of software weaknesses,” said Sanii.

“AI-assisted tools can help attackers discover and exploit vulnerabilities much faster.”

Source: https://mybroadband.co.za/news/cryptocurrency/647556-man-unlocks-r6-5-million-after-ai-recovers-bitcoin-password-lost-11-years-ago.html?utm_source=newsletter