Cetus Protocol, a decentralized exchange (DEX) operating on the Sui and Aptos blockchains, has suffered a significant security breach resulting in the loss of approximately $223 million in digital assets.
This incident ranks among the largest decentralized finance (DeFi) exploits to date and is particularly galling as according blockchain security firm Dedaub, the security vulnerability at fault was highlighted over two years ago in an earlier Ottersec security audit.
The Exploit: A Critical Overflow Vulnerability
Dedaub conducted a post-mortem analysis revealing that the attackers exploited a critical overflow flaw in Cetus Protocol’s automated market maker (AMM) logic.
Specifically, the flaw involved an improper handling of large numerical inputs, where a miswritten condition failed to correctly process the most significant bits (MSB) of these inputs. As a result, attackers were able to deposit minimal amounts of tokens while receiving disproportionately large liquidity credits, which they then used to drain substantial assets from the liquidity pools.
This vulnerability was particularly concerning because Dedaub notes that it had previously been identified during an early 2023 audit by another blockchain security firm, Ottersec, when Cetus was operating on the Aptos blockchain. Despite this, the flaw remained unaddressed, highlighting a lapse in the protocol’s security measures.
Immediate Response and Fund Recovery Efforts
In the immediate aftermath of the breach, Cetus Protocol, in collaboration with the Sui Foundation and network validators, has done what it can to mitigate the damage. Approximately $163 million of the stolen assets were successfully frozen by Sui network validators and ecosystem partners on the same day as the hack.
Many in the community have criticized the decision to allow nodes to step in and centrally block on-chain activity.
“SUI validators are actively censoring transactions across the blockchain. This completely undermines the principles of decentralization and transforms the network into nothing more than a centralized, permissioned database,” wrote user X @ItsDave_ADA. This and many other comments on the post explaining why the freeze was conducted, have aggressively criticize it.
The incident has sparked a debate within the crypto community regarding the balance between decentralization and security. The decision by Sui network validators to freeze the stolen funds, while effective in mitigating losses, has been criticized by some as undermining the principles of decentralization. To facilitate the recovery of the remaining funds, Cetus proposed an on-chain vote to implement a protocol upgrade aimed at retrieving the frozen assets. Additionally, Cetus has offered a $5 million bounty to the hacker in exchange for the return of the stolen funds.
Source: https://bravenewcoin.com/insights/cetus-hack-the-familiar-lax-crypto-security-playbook-strikes-again