2021 was the year of rising adoption and bigger interest in the cryptocurrency space. The total value locked (TVL) reached more than $200B. However, hackers started to catch up and there were some of the biggest hacks in the history of cryptocurrencies.
Poly Network Hack - $600M
The Poly Network Hack happened in August 2021 and was the biggest cryptocurrency exploit of all time. Assests worth more than $600M were stolen from the protocol.
The cryptocurrency got together to stop the funds being used and laundered by the hacker. Surprisingly, the hacker decided to return the funds and was even offered a role as 'chief security adviser' by Poly Network. Furthermore, the hacker received a 161ETH bounty.
BitMart is a centralized exchange which was hacked in December 2021. Two of the platform's hot wallets were compromised and funds worth $196M, mostly 'memecoins', were stolen.
Little is still known about the cause of the exploit.
Cream Finance - $148M
The DeFi platform was hacked twice in 2021. The first hack occured in August where $18M in funds were stolen. The second hack in October made the DeFi platform lose another $130M.
In total, the hacker managed to get away with 2,760 ETH, 76 BTC, $10M in stablecoins and other assets.
Vulcan Forged - $140M
In December 2021, the play-to-earn NFT game was exploited for a total of $140m. A majority of assets were taken from users wallets. Following the hack, the team reimbursed users from its treasury.
Badger Finance - $120M
Badger Finance was hacked in December when BadgerDAO faced a 'front-end' attack. More than $120M in ETH and BTC were stolen from the platform.
Popular crypto platform Celsius was also affected by compromised smart contracts, reportedly losing 896 BTC.