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Hackers stole over $4 billion in cryptocurrencies this year — Here’s a full list of the biggest crypto heists in 2021

  • Hackers made off with more than $4 billion worth of cryptocurrencies in 2021, according to a report by Crystal Blockchain.
  • Decentralised finance (DeFi) saw the biggest jump in thefts — a sector that’s new and still growing, making it an attractive target for thieves.
  • The Poly Network exploit, which saw over $610 million in crypto coins siphoned off, isn’t only the biggest DeFi attack of the year, but the biggest in all of DeFi history.
Crypto markets may be the next generation of financial services but the same old risks still apply — where there’s money, there’s people trying to steal it. And, this year hackers got away with $4.25 billion. That is almost a tripling over 2020, when around $1.49 billion in crypto assets were stolen. Comparitech compiled data to show that 2021 saw six of the ten costliest crypto hacks of all time.

And, the fastest growing way to steal crypto this year was through hacking decentralised finance (DeFi) protocols with it alone accounting for $1.4 billion of the total crypto funds stolen this year, according to a report by analytics firm Crystal Blockchain. “This can be explained by the fact that the technology is new and still has a lot of vulnerabilities,” it said.

In fact, the biggest DeFi breach to date occurred in 2021 with $610 million worth of cryptocurrencies swiped from the Poly Network by a hacker who was only looking to ‘prove a point’. “DeFi attacks will continue increasing, while the DeFi industry continues building better security systems and hackers continue to do their best to break these systems,” said Crystal’s report. Attesting to the industry’s efforts, over half of such losses due to DeFi hacks could be recovered this year.

The growth in the popularity of non-fungible tokens (NFTs) has also spurred fresh activity where bad actors are finding new and innovative ways to trick people into buying fake digital assets or investing in scams.

From leaked word documents to stolen passwords, here’s a quick look at the 10 biggest cryptocurrency hacks of 2021: