Ethereum's second 'Pectra' test contains a vulnerability that could delay upgrade

summary

• Ethereum’s Pectra upgrade Sepolia encountered an empty block problem during testing.

• This is the second time the testnet has had issues following the previous Holesky test failure.

• Both of these issues were caused by test configuration errors, not problems with Pectra itself.

• Some in the ethereum community believe the upgrade should be tested more before it goes live.

On Wednesday, ethereum developers initially celebrated a seemingly successful test of Pectra on the Sepolia test network, the blockchain’s most significant upgrade since 2024. However, a few hours into the test, Sepolia began experiencing errors.

This is the second buggy test of the much-anticipated Pectra upgrade, which is designed to improve ethereum’s efficiency, user experience and validator system. The issues have led some developers to call for a delay to the upgrade.

Wednesday’s Sepolia test is expected to be the final step before Pectra goes live on the Ethereum mainnet. Initially, the test appeared to be successful, but later, developers noticed empty blocks were added to the chain.

The Ethereum Foundation blamed the problem on “an issue with the Sepolia permission deposit contract” which “prevented many execution layer clients from including transactions in blocks.” In other words, the problem stemmed from a misconfiguration specific to the Sepolia test, not a flaw in Pectra itself.

Developers at the Ethereum Foundation said they “identified the root cause within minutes” and deployed a fix to restore normal functionality of the network.

Still, the test raised concerns about whether Pectra had been adequately tested. A previous test on ethereum’s Holesky testnet also encountered configuration issues, which were caused by a misconfigured validator.

“I do think the events on the Holesky and Sepolia testnets warrant delaying Pectra mainnet activation,” said Christine Kim, vice president of research at Galaxy Digital, noting that while developers may feel ready, the broader ethereum ecosystem — including major smart contract applications and wallet providers — needs to be ready.

Kim suggested that ethereum’s developers “take the time to build additional testing infrastructure” before launching the upgrade.

Ethereum core developers will meet on March 7 to set an official release date for Pectra. Any delay is likely to be controversial among ethereum supporters, who are already on edge due to lagging ETH token prices, leadership turmoil at the Ethereum Foundation and growing competition from networks like Solana.