Are there any real-world examples of successful 51% attacks on cryptocurrencies?

7 answers

• MessielFeb 21, 2022 · 4 years ago
  Yes, there have been a few notable examples of successful 51% attacks on cryptocurrencies. One such example is the attack on the Ethereum Classic (ETC) blockchain in January 2019. The attacker was able to control more than 51% of the network's mining power and successfully carried out a series of double-spending attacks, resulting in the theft of millions of dollars worth of ETC. This incident highlighted the vulnerability of cryptocurrencies to 51% attacks and raised concerns about the security of blockchain networks.
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• Alfan Ismail AlfanSep 20, 2021 · 5 years ago
  Unfortunately, there have been real-world examples of successful 51% attacks on cryptocurrencies. One notable case is the attack on the Verge (XVG) blockchain in April 2018. The attacker gained control of more than 51% of the network's mining power and was able to manipulate the blockchain, resulting in the unauthorized creation of new coins. This incident raised concerns about the security and decentralization of the Verge network.
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• OrangeQuackApr 07, 2026 · 3 months ago
  As an expert in the field, I can confirm that there have been instances of successful 51% attacks on cryptocurrencies. One example is the attack on the Bitcoin Gold (BTG) blockchain in May 2018. The attacker controlled more than 51% of the network's mining power and carried out a double-spending attack, resulting in the theft of approximately $18 million worth of BTG. This incident highlighted the importance of network security and the need for robust consensus mechanisms.
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• Emerson Martins BritoDec 20, 2025 · 6 months ago
  While I cannot speak specifically about BYDFi, I can tell you that there have been real-world examples of successful 51% attacks on cryptocurrencies. These attacks occur when a group or individual gains control of more than 51% of the network's mining power, allowing them to manipulate the blockchain and carry out malicious activities. It is crucial for cryptocurrency networks to have strong security measures in place to prevent such attacks.
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• Foged KureMay 15, 2025 · a year ago
  Yes, there have been instances of successful 51% attacks on cryptocurrencies. One example is the attack on the ZenCash (ZEN) blockchain in June 2018. The attacker controlled more than 51% of the network's mining power and was able to reorganize the blockchain, resulting in the double-spending of coins. This incident highlighted the need for increased security measures and the importance of decentralized consensus in cryptocurrency networks.
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• Maria José Oliveira GuimarãesFeb 28, 2021 · 5 years ago
  Absolutely! There have been real-world examples of successful 51% attacks on cryptocurrencies. One notable case is the attack on the Feathercoin (FTC) blockchain in June 2013. The attacker controlled more than 51% of the network's mining power and carried out a series of double-spending attacks, resulting in significant financial losses for users. This incident served as a wake-up call for the cryptocurrency community to strengthen network security and explore alternative consensus mechanisms.
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• one1 japanSep 16, 2025 · 9 months ago
  Yes, there have been instances of successful 51% attacks on cryptocurrencies. One example is the attack on the Litecoin Cash (LCC) blockchain in May 2018. The attacker controlled more than 51% of the network's mining power and carried out a series of double-spending attacks, resulting in the theft of approximately $250,000 worth of LCC. This incident highlighted the need for increased security measures and the importance of community vigilance in detecting and preventing such attacks.
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