Arkham Intelligence Suggests LuBian Bitcoin Hack May Be Largest Crypto Heist Unreported for Years

• LuBian lost 127,426 BTC in a stealth attack that went unreported for years.

• The stolen Bitcoin is now valued at approximately $14.5 billion, emphasizing the scale of the breach.

• Arkham Intelligence identified the hack through blockchain analysis and OP_RETURN messages sent by LuBian to hacker wallets.

LuBian’s $3.5B Bitcoin hack is the largest crypto heist, uncovered by Arkham Intelligence. Discover how the breach happened and its impact on crypto security today.

How Did the LuBian $3.5 Billion Bitcoin Hack Occur?

The LuBian Bitcoin hack took place on December 28, 2020, targeting the Chinese mining pool which was then the sixth-largest BTC miner. Hackers exploited a weakness in LuBian’s private key generation algorithm, allowing a brute-force attack that stole 127,426 BTC. This vulnerability went unnoticed, and the attack remained undisclosed until Arkham Intelligence revealed it years later.

What Role Did OP_RETURN Messages Play in Uncovering the Hack?

LuBian attempted to trace the stolen funds by embedding OP_RETURN messages in 1,516 transactions sent to hacker-controlled wallets, costing about 1.4 BTC. These messages helped Arkham Intelligence map the flow of stolen Bitcoin and confirm the scale of the breach. This forensic approach highlights the importance of blockchain transparency in tracking illicit activity.

Funds stolen from LuBian through multiple transactions. Source: Arkham Intelligence

How Does the LuBian Hack Compare to Other Major Crypto Heists?

Before this revelation, the February 2025 ByBit exchange hack, which resulted in a $1.5 billion loss, was considered the largest crypto breach. ByBit’s hack involved malware on a SafeWallet developer’s machine, allowing attackers to access sensitive systems stealthily. In contrast, LuBian’s hack exploited cryptographic weaknesses, leading to a far larger loss in Bitcoin value.

What Are Other Notable Crypto Heists in Recent History?

In April 2025, an elderly victim lost $330 million in Bitcoin through a social engineering attack, with funds laundered across 300 wallets. This incident ranks as the fifth-largest crypto heist. These events underscore the critical need for robust cybersecurity and private key management in the crypto ecosystem.

The OP_Return messages sent from LuBian to the hacker addresses. Source: Arkham Intelligence

What Lessons Does the LuBian Hack Teach About Crypto Security?

Private key management is paramount in preventing crypto theft. LuBian’s use of an algorithm vulnerable to brute-force attacks allowed hackers to access their funds. This incident stresses the importance of using strong, random number generators for key creation and maintaining vigilant security practices.

How Can Crypto Users Protect Themselves Against Similar Attacks?

Users should rely on hardware wallets and multi-signature setups to safeguard assets. Regular security audits and avoiding predictable key generation algorithms are essential. Experts from Arkham Intelligence emphasize proactive safety measures to mitigate risks in the evolving threat landscape.

Frequently Asked Questions

What made the LuBian hack the largest crypto heist?

The LuBian hack involved stealing 127,426 BTC, worth $3.5 billion at the time, surpassing all previous crypto thefts in volume and value.

Why did the LuBian hack go unreported for years?

Neither LuBian nor the hackers disclosed the breach, and the vulnerability was only revealed through blockchain forensic analysis by Arkham Intelligence.

What security flaws did the hackers exploit in LuBian?

Hackers exploited a weak private key generation algorithm susceptible to brute-force attacks, allowing unauthorized access to LuBian’s Bitcoin wallets.

Key Takeaways

• LuBian’s $3.5 billion Bitcoin hack: The largest crypto theft to date, uncovered years later by Arkham Intelligence.
• Security vulnerability: Weak private key generation algorithms can lead to catastrophic losses.
• Proactive protection: Employ hardware wallets, multi-signature setups, and strong cryptographic practices to safeguard assets.

Conclusion

The LuBian hack stands as a stark reminder of the critical importance of robust crypto security measures. With stolen Bitcoin now valued at over $14 billion, this breach highlights vulnerabilities in private key management and the need for continuous vigilance. As the crypto landscape evolves, users must prioritize advanced security protocols to protect their digital assets and maintain trust in decentralized finance.