$625 million worth of cryptocurrency has been stolen in a fearless attack on Axie Infinity, an NFT -based and blockchain-based online video game developed by Vietnamese studio Sky Mavis, known for its in-game economy which uses Ethereum-based cryptocurrencies.
Axie Infinity is built on the Ronin Network, an Ethereum-linked sidechain developed by Sky Mavis. A sidechain is a separate blockchain which runs in parallel to Ethereum Mainnet and operates independently.
Axie Infinity is a video game in which players collect and mint NFTs which represent axolotl-inspired digital pets.
The Ronin bridge has been exploited for 173,600 Ethereum and 25.5M USDC, said the Ronin Network, in a newsletter, this week's Tuesday.,
Sky Mavis says it’s working with law enforcement to recover 173,600 Ethereum (currently worth around $600 million) and 25.5 million USDC (a cryptocurrency pegged to the US dollar) from the culprit, who withdrew it from the network on March 23rd.
According to Sky Mavis, an attacker used hacked private security keys to compromise the network nodes that validate transfers to and from the Ronin blockchain. That let the attacker quietly withdraw large quantities of Ethereum and USDC. The transfer was discovered today — nearly a week later — when another user attempted to withdraw 5,000 Ethereum through the bridge.
Ronin Network said, "We are in the process of conducting a thorough investigation; working with Chainalysis to monitor the stolen funds and Crowdstrike to handle forensics and the setup of surveillance tools."
It is being speculated that this is the largest hack to date of "decentralized finance" (DeFi) networks. Last year in August, Hackers stole more than $600 million in Ethereum and other cryptocurrencies. This is the biggest theft ever in the decentralized finance or DeFi space.