Ronin is the sidechain of the popular crypto video game Axie Infinity. The bridge connecting Ronin to the Ethereum blockchain had over $620 million in Ether stolen. This is the most serious DeFi hack ever, and the funds are still in the possession of the hacker.
The Ethereum-based sidechain for blockchain game Axie Infinity Ronin was hacked for over $620 million in Ether (ETH) and USD Coin (USDC). According to an official statement, the attacker used compromised private keys from Sky Mavis Team to capture withdrawals from Ronin Bridge in two transactions. The attack was discovered a week later when a user failed to withdraw 5,000 Ether. This is the largest hack in the history of decentralized finance (DeFi), eclipsing even the theft of $611 million from the Poly Network last year.
Over $620 million loot
According to the blog post, the Ronin sidechain consists of nine validation nodes. Five of the nine validation signatures are required to process a deposit or withdrawal from the Ronin network onto the Ethereum blockchain. This was to prevent a central party from having control over all user funds. However, the attacker managed to take control of the four Ronin validators from developer team Sky Mavis and the Axie DAO's validator. These were apparently all located in the same system to which the hacker was able to gain access.
In total, the hacker captured 173,600 ETH and 25.5 million USDC, which at the time of writing is worth more than $620 million. Several million dollars have since been moved from the attacker's wallet address, including to centralized exchanges such as FTX and Binance.
Ronin exchange is stopped
Meanwhile, Ronin Bridge and the Katana decentralized exchange (DEX) have been halted to pave the way for investigations. Axie Infinity creator Sky Mavis is now working with law enforcement, forensic cryptographers, and the investors to ensure that all funds are recovered or refunded.
"We are working directly with various government agencies to ensure that the criminals are brought to justice. We are in the process of discussing with Axie Infinity / Sky Mavis stakeholders how best to proceed and ensure that no user funds are lost. Sky Mavis has come to stay and we will continue to expand." - Blogpost Sky Mavis
