Ronin’s $612 million hack exposes these vulnerabilities of cross-chain bridges

ambcrypto.com:

For quite some time now, multi-chain or cross-chain technology has become a holy grail in the cryptocurrency development space. People want to transact with other blockchains by leveraging bridges to different ecosystems. For example, Ethereum co-founder and developer Vitalik Buterin tweeted a link to a Reddit post on 8 January, 2022.

He discussed his belief in a multi-chain future but expressed doubt concerning cross-chain ecosystems. In his argument, Buterin cited the “fundamental security limits of bridges” as the key reason for his disapproval of a cross-chain environment.

Although, he didn’t expect hiccups to arise any time soon. But note this – as the volume of cryptocurrency held in bridges grew, the incentive to attack them too. 

Since then, hackers have compromised more than $1B despite such warnings. 

Ronin Network, an Ethereum-based sidechain created by Axie Infinity developer Sky Mavis is trending for the wrong reason. Hackers stole nearly $600 million worth of Ethereum & USDC tokens from the Ronin Bridge that connected different blockchains.

According to a blog post published by the Ronin Network’s official Substack, the exploit affected Ronin Network validator nodes for Sky Mavis, the publishers of the popular Axie Infinity game, and the Axie DAO.

— Ronin (@Ronin_Network) March 29, 2022

According to an official statement on Tuesday, the attacker “used hacked private keys to forge fake withdrawals” from the Ronin bridge contract in two transactions. Per the blog post, the Ronin sidechain consisted of nine validator nodes.

Five out of the nine validator signatures are required to process a deposit or