Arkham Detects Bitcoin Theft Case in 2020 Worth 14.5 Billion USD

In the largest undisclosed cryptocurrency theft in history, blockchain analytics firm Arkham Intelligence has revealed an astonishing theft of 127,426 Bitcoin, worth $14.5 billion today, from the Chinese mining group LuBian. The theft, which occurred in December 2020, went undetected for years while rumors of LuBian's sudden disappearance in early 2021 circulated. However, the latest findings from Arkham indicate that this is not a quiet shutdown or government action - but rather a serious breach potentially caused by a weak private key algorithm. The attacker has not moved the stolen BTC for over a year, leaving behind many mysteries, technical errors, and unanswered questions. What Has Arkham Intelligence Discovered? Arkham Intelligence has brought a four-year-old cryptocurrency mystery back into the spotlight. According to this blockchain analytics company, a total of 127,426 BTC - worth approximately $14.5 billion today - was stolen from the Chinese mining group LuBian in December 2020. At that time, the value of the stolen Bitcoins was around 3.5 billion dollars, making it the largest theft known in the history of cryptocurrency based on USD value at the time it occurred.

While hacks like Mt. Gox involved multiple coins more than (744.000 BTC), the price of Bitcoin at that time meant those losses were worth hundreds of millions, not billions. Who or what is LuBian? LuBian is not just a small mining group. Launched in April 2020, just a few months later, it became the sixth largest mining group on the Bitcoin network. On its website, LuBian proudly claims to be the "safest and most productive mining group in the world." But then, at the beginning of 2021, it disappeared without any explanation. At that time, many theories were put forward. It is possible that Chinese regulators shut it down. Or it may have been privatized. But according to the latest research from Arkham, the truth may be darker — LuBian did not escape; it was wiped out by a major cyberattack, draining almost its entire Bitcoin reserves in just a few days. How Did the Hack Occur? This is when things start to get complicated. Arkham believes that the attacker exploited a vulnerability in LuBian's private key generation algorithm. Simply put, LuBian used an unsafe method to generate private keys, which could utilize predictable patterns or be attacked using brute-force methods. On December 28, 2020, hackers were reported to have stolen over 90% of LuBian's Bitcoin. The very next day, an additional 6 million in BTC and USDT was withdrawn from LuBian's Bitcoin Omni Layer address. This was not just a single breach — it was a coordinated and ongoing attack. What Happened After the Theft? LuBian is not silent at all. It has used the OP_RETURN field of Bitcoin — a seldom-used feature that allows embedding data into transactions — to send direct messages to the hackers. The content of the message resembles a digital ransom note, calling the attacker a potential white hat hacker and offering a reward if the stolen assets are returned. Here is a part of the content that LuBian has written: "To the white hat individuals who are saving our assets, you can reach out to us... to discuss the return of your assets and rewards." But until now, there has been no information returned. Interestingly, no stolen BTC has been moved since July 2024, suggesting that the attacker is either extremely patient, extremely cautious, or simply unable to move this money without being detected. LuBian did not lose everything. Approximately 11,886 BTC — currently worth 1.35 billion dollars — has been secured and still resides in their known cryptocurrency wallets. That is still a massive cryptocurrency asset, but it still pales in comparison to the amount stolen. This incident is a wake-up call for the mining ecosystem. It shows that even large and successful mining groups can collapse overnight if they neglect best key management practices. Unlike smart contract exploits or scams, this attack targeted the core of cryptocurrency security: private key creation. That's really rare. And really scary. Will the Stolen BTC Ever Be Recovered? This is unlikely to happen. These coins have not been laundered or mixed — so far — but their enormous volume makes them dangerous. Moving even a small fraction of the 127,426 BTC would immediately attract the attention of all major exchanges, law enforcement agencies, and blockchain analysts around the world. Hackers may try to wait until blockchain monitoring activities become less effective, but with platforms like Arkham and Chainalysis becoming more advanced, that opportunity will become increasingly narrow. What Comes Next? Arkham's report has reignited interest in the case. If law enforcement agencies were previously unaware of the hack, they are certainly informed now. And if the attacker moves BTC, it will trigger real-time alerts across the entire cryptocurrency intelligence community. Meanwhile, the lesson learned is very clear: cryptocurrency security is not just about protecting against phishing emails or smart contract bugs — it also starts with basic principles like private key control. A faulty algorithm can lead to billions of dollars in losses.