Ethereum
Ethereum developers have canceled the planned October 26 activation of the Glamsterdam upgrade on the Hoodi testnet after security issues identified by blockchain cybersecurity firm ChainSecurity prompted a reassessment of the rollout. The decision removes the previously scheduled testing milestone and leaves the next hard fork without a finalized public test date, complicating efforts to establish a mainnet deployment timeline.
Christine D. Kim, founder of crypto research and advisory firm Protocol Watch, reported the cancellation on October 22, attributing the decision to ChainSecurity’s findings. The timing is significant: Hoodi’s upgrade had been scheduled just four days later, while Ethereum’s core developers were preparing to discuss potential mainnet deployment dates.
The security concerns center on EIP-8037 and EIP-8038, two Glamsterdam proposals that modify Ethereum’s gas-charging model for creating and accessing state. In an analysis published on October 13, ChainSecurity warned that these changes could alter smart contract behavior under failure conditions, even when the underlying contract code remains unchanged.
The firm highlighted a potentially consequential change in execution behavior: an operation that previously reverted could instead complete. This distinction matters because smart contracts and applications may rely on failed operations reverting as part of their error-handling logic. If those assumptions no longer hold under the revised gas model, operations designed to be retried could instead enter states that produce permanent failures.
The findings do not establish that the proposed upgrade has caused an exploit or that deployed contracts have already suffered losses. Rather, they identify a compatibility and execution risk that developers need to understand before the changes are activated. Addressing such risks before deployment is particularly important for protocol upgrades, where changes to execution rules can affect applications across the network without requiring developers to modify their existing code.
The cancellation therefore represents a change in the upgrade’s readiness assessment, not simply a scheduling adjustment. Until developers understand the affected failure paths and determine whether the proposals require revisions or additional safeguards, proceeding with the testnet activation could leave important compatibility questions unresolved.
The response was reflected in Ethereum’s client and network configuration work on October 22. Before the All Core Devs Execution call, security researcher pcaversaccio urged developers on GitHub to review ChainSecurity’s analysis, while noting that the decision ultimately rested with Ethereum’s core development team.
Kim subsequently advised node operators to revert to an earlier release that did not include the Hoodi upgrade or wait for further updates removing it. Besu developers, who maintain one of Ethereum’s major execution clients, merged a pull request titled “Unschedule Amsterdam on Hoodi” on October 22.
The change does not automatically update every node already running the affected software. According to the reported implementation details, nodes operating on Besu 26.10.0 will continue to activate the upgrade until the newer release is installed. This makes software-version management an immediate operational consideration for node operators, even though the scheduled activation has been withdrawn.
Ethereum Foundation DevOps team member Barnabas Busa also removed the upgrade schedule from Hoodi’s shared network configuration files. The rollback removed the programmed October 26 activation for Amsterdam, the upcoming Gloas fork at epoch 132,352, and the planned increase in Hoodi’s gas limit to 200 million at the same epoch. The network configuration was returned to its earlier state, removing the scheduled fork events and leaving the next testing date unresolved.
The broader consequence is uncertainty around the mainnet rollout. The Ethereum Foundation announced the Hoodi testnet schedule on October 16, and the October 22 developer agenda had included three potential mainnet deployment dates for Glamsterdam: December 1, December 8 and December 9. Those dates were under consideration pending successful Hoodi testing, rather than representing a finalized launch commitment.
With the testnet activation canceled, the basis for selecting among those dates has weakened. A revised schedule will depend on how developers respond to the security findings, whether changes to the proposals are needed, and when a new testing window can be established. Even if the technical issues prove straightforward to resolve, the upgrade will still need to progress through the relevant testing and review process before a mainnet date can be confirmed.
Glamsterdam remains a significant protocol upgrade because it includes changes intended to affect Ethereum’s block-building and execution architecture. EIP-7732 introduces proposer-builder separation at the protocol level, while EIP-7928 adds block-level access lists. The upgrade had already been undergoing testing on Sepolia since October 6, meaning its development and validation process extends beyond the canceled Hoodi deployment.
These features should be distinguished from the immediate security concerns surrounding EIP-8037 and EIP-8038. The cancellation does not, by itself, establish that all Glamsterdam components are affected by the reported problems. Instead, it demonstrates how issues involving a subset of protocol changes can delay a broader release when the components are scheduled to activate together.
For the market, the immediate implication is primarily uncertainty around Ethereum’s development timetable rather than a confirmed change to the network’s live operating conditions. The cancellation does not itself indicate a failure of Ethereum’s current mainnet or establish a direct effect on ETH’s price. However, an extended delay could affect expectations around when the protocol’s planned architectural changes will become available.
The more important signal will be the quality and pace of the technical response. A revised Hoodi schedule accompanied by a clear resolution of the identified failure scenarios would provide a basis for reconsidering the December deployment window. Conversely, additional changes to the proposals or repeated testing delays would make the original mainnet dates less reliable.
The next milestones are therefore a clarified remediation plan, a new Hoodi activation date and evidence that the revised upgrade behaves as intended under the failure conditions identified by ChainSecurity. Until those steps are completed, December 1, December 8 and December 9 should be treated as previously discussed possibilities rather than confirmed launch dates.
