Ethereum Scaling Solution Optimism Patches ‘Critical Bug’ that Allowed Unlimited Ether Minting

A close shave for the Layer-2 Ethereum scaling solution Optimism, as it discloses it had patched a critical bug earlier this month.

Avoiding a Potential Disaster

In a blog post published Thursday, the optimistic rollup scaling solution for Ethereum stated the critical bug was discovered in the project’s fork of Geth, an Ethereum implementation.

Regarding the bug, the team said:

“The bug made it possible to create ETH on Optimism by repeatedly triggering the SELFDESTRUCT opcode on a contract that held an ETH balance.”

Fortunately, the bug was identified by Orchid VPN co-founder and CTO, Jay Freeman, before it could be exploited by any nefarious elements.

Freeman was awarded a bug bounty of about $2 million for identifying the bug and informing the Optimism team about the same. The developer published a separate blog post where he goes deeper into the finer details of the bug.

Per the official post-mortem report by Optimism, the bug was not exploited except for the one occasion when an Etherscan employee accidentally triggered it. However, no usable excess ETH was generated to make any money.

The Optimism team adds that a fix for the issue was tested and quickly deployed to Optimism’s Kovan and Mainnet networks soon after the official confirmation of the bug’s existence. The team coordinated with Ethereum infrastructure provider Infura, QuickNode, and Alchemy to quickly ship the bug fix on the two networks.

As an additional security measure, the team alerted several vulnerable Optimism forks and bridge providers about the significance of the bug. Accordingly, all the projects informed of the bug have applied the required fix.

Optimism TVL Growing at a Steady Pace

For the uninitiated, Optimism is an optimistic rollup solution like Arbitrum, aimed toward eliminating Ethereum’s scalability woes and aiding in bringing down the cumbersome gas prices.

At large, there are two distinct types of solutions that promise to scale Ethereum, Optimistic Rollups and ZK (zero-knowledge) Rollups.

Both the solutions aggregate transactions on their own networks before finally settling the transactions on the base Ethereum chain to ensure complete immutability.

Over time, scaling solutions such as Optimism aim to become the de-facto transaction execution networks for Ethereum to mitigate the burden on the base layer. Scaling solutions only interact with Ethereum for security and transaction settlement purposes.

According to data from Ethereum Layer-2 scaling solution tracker L2BEAT, Arbitrum currently leads the chart with a TVL of $3.30 billion. Currently, Optimism ranks fourth with a TVL of $479 million.

It’s still early days for Ethereum scaling solutions, and as an increasing number of quality Layer-2 alternatives arrive in the market, expect TVL to follow solutions that offer the best security, user experience, and affordable transactions to its users.

Although Optimism managed to avoid a potential catastrophe with the early detection of the critical bug, other projects have not been quite as lucky.

As previously reported by crypto.news, Wormhole, a bridge to move digital assets between Solana and Ethereum was exploited to the tune of 120k ether – worth more than $300 million at the time – in what turned out to be one of the largest DeFi hacks to date.