Ethereum Delays Glamsterdam Testnet Launch Over Potential Contract Failures

Ethereum developers have postponed the planned Glamsterdam upgrade on the Hoodi testnet after security researchers identified a potential flaw in how the proposed gas rules could affect existing smart contracts.

The activation was scheduled for October 26 at 17:42:48 UTC. Developers called off the rollout during Thursday’s All Core Devs Execution meeting to investigate how the new gas-accounting system might change the behavior of contracts already operating on Ethereum.

No replacement date has been set.

Proposed Gas Rules Could Change Failure Handling

The issue involves EIP-8037, which revises the gas costs associated with creating new records in Ethereum’s database. The proposal is designed to help control blockchain state growth as the network expands its transaction capacity.

Security firm ChainSecurity detailed the concern in research published October 13. Its analysis found that EIP-8037, when combined with EIP-8038, could affect what happens when a contract called by another smart contract runs out of gas.

Some contracts are built to handle unsuccessful calls without stopping the entire process. They may store a failure record, block additional attempts or move to another execution step. In certain designs, developers expect the remaining gas to be insufficient for that follow-up action, causing the entire transaction to revert and undo its changes.

The proposed accounting rules could undermine that expectation.

Researchers Identify Two Potential Risks

Under Glamsterdam’s proposed rules, gas used to create certain database records may be restored when those changes are reversed. This could leave enough gas for a contract to finish processing a failed operation rather than triggering a complete rollback.

As a result, a failure-handling action could become permanent even when the original transaction would previously have been reverted.

ChainSecurity also highlighted the possibility of operations becoming more expensive. Its calculations showed that creating a new storage slot could cost 110,020 gas after a separate allowance is exhausted, compared with 22,100 gas under the current rules.

That difference could cause a contract to run out of gas while performing an operation that would have succeeded under the previous accounting system.

Although the researchers demonstrated these mechanisms, they have not publicly confirmed that a major live protocol is exploitable. The findings instead point to potential compatibility and execution risks that require further investigation.

Hoodi Upgrade and Gas Limit Increase Postponed

Glamsterdam includes several Ethereum protocol changes, including a new framework for selecting block builders and improvements intended to support larger blocks.

The upgrade completed its Sepolia testnet activation on October 6. Hoodi was scheduled to follow as the next public testing environment, alongside a planned increase in its gas limit to 200 million.

Both changes are now on hold while developers assess the security findings and determine whether adjustments are needed.

Ethereum Has Yet to Set a Mainnet Date

No official mainnet activation date has been announced for Glamsterdam. The Hoodi delay does not indicate that Ethereum contracts are currently being exploited through the proposed changes; it reflects concerns about how those contracts could behave if the new rules are introduced.

Developers must resolve the outstanding questions and complete further testing before setting a new rollout schedule.