Crypto heist: Hackers steal $625 m from video game Axie's blockchain

In one of the biggest ever cryptocurrency attacks, hackers stole two cryptocurrencies – Ethereum and USDC worth about $625 million targeting the Ronin Network, a side chain of the Ethereum blockchain, that supports the popular video game Axie Infinity.

In a blog post published on Tuesday (March 29), Ronin Network, developed by Axie Infinity publisher Sky Mavis, said there was a security breach on March 23 and was discovered only on March 29.

“There has been a security breach on the Ronin Network. Earlier today (March 29), we discovered that on March 23rd, Sky Mavis’s Ronin validator nodes and Axie DAO validator nodes were compromised resulting in 173,600 Ethereum and 25.5M USDC drained from the Ronin bridge in two transactions,” Ronin said.

Important announcement regarding a security breach on the Ronin Network. https://t.co/88TilOGTX6

— Axie Infinity🦇🔊 (@AxieInfinity) March 29, 2022

USDC is a stablecoin pegged to the US dollar.

“The attacker used hacked private keys in order to forge fake withdrawals. We discovered the attack this morning after a report from a user being unable to withdraw 5k ETH from the bridge. The Sky Mavis team discovered the security breach on March 29th, after a report that a user was unable to withdraw 5k ETH from the bridge,” it added.

Axie Infinity co-founder Jeff Zirlin termed it as “one of the bigger hacks in history.”

Ronin said most of the hacked funds are still in the hacker’s wallet and they were in the process of conducting a thorough investigation. “Five validator private keys were hacked; 4 Sky Mavis validators and 1 Axie DAO,” it stated.

Listing out the actions taken after the attack, Ronin said, “We are working directly with various government agencies to ensure the criminals get brought to justice… we are actively taking steps to guard against future attacks. To prevent further short term damage, we have increased the validator threshold from five to eight.”

It said that the Ronin Bridge was temporarily paused to ensure no further attack vectors remain open. Also, Binance has also disabled their bridge to/from Ronin to err on the side of caution. The bridge will be opened up at a later date once we are certain no funds can be drained.

Axie Infinity is a video game linked to non-fungible tokens (NFTs).

In 2021, according to CNN Business, an anonymous hacker stole roughly $600 million in cryptocurrency from Poly Network, a decentralised finance network, in what was called the largest crypto heist in history. The hacker later gave it back.