Ethereum Glamsterdam Upgrade Delayed as Security Researchers Flag Smart Contract Risks
Ethereum developers have postponed the Glamsterdam hard fork on the Hoodi testnet following security concerns involving existing smart contracts. The upgrade was scheduled for October 26, 2026, but developers canceled the activation during an October 22 coordination meeting. The decision gives researchers additional time to investigate potential vulnerabilities before proceeding with the network upgrade.
Smart contract security firm ChainSecurity identified risks linked to proposed changes in Ethereum’s gas accounting system. Researchers reportedly discovered 13 real-world cases involving potentially affected contracts. The firm is coordinating responsible disclosures with relevant projects while the Ethereum Foundation evaluates the broader security implications.
Security Researchers Identify Potential Contract Vulnerabilities
The concerns primarily involve EIP-8037 and EIP-8038, two proposals that modify Ethereum’s gas pricing and state management. These changes could alter how existing smart contracts behave when transactions encounter insufficient gas.
ChainSecurity’s technical analysis explains that certain failed operations could produce unexpected outcomes under the proposed rules. In some circumstances, contracts might permanently record failed transactions that previously would have reverted, potentially preventing users from retrying legitimate operations.
The researchers have encouraged development teams to examine their smart contracts for dependencies on existing gas behavior. However, the affected projects and contract addresses have not been publicly identified. No confirmed financial losses have been disclosed in connection with the findings.
Ethereum Developers Reassess Glamsterdam Deployment
The Glamsterdam upgrade forms part of Ethereum’s broader effort to improve scalability, transaction processing, and network efficiency. Its major features include enshrined proposer-builder separation and block-level access lists, which aim to improve block production and validation.
Ethereum successfully activated Glamsterdam on the Sepolia testnet on October 6. Developers subsequently scheduled the Hoodi deployment for October 26, alongside an increase in the testnet’s gas limit to 200 million.
However, the latest decision removes both the scheduled activation and the accompanying gas-limit adjustment. Hoodi node operators and validators must now review their software configurations to ensure compatibility with the revised schedule.
Mainnet Timeline Remains Uncertain
The postponement introduces uncertainty around Glamsterdam’s eventual deployment on Ethereum mainnet. Developers had considered early December activation dates, subject to successful testing on Hoodi.
The Ethereum Foundation has not announced a replacement testnet activation date or confirmed a mainnet launch schedule. Meanwhile, developers continue investigating the security findings and assessing whether additional protocol changes are necessary.
The delay highlights the importance of testing protocol upgrades against existing applications before introducing changes to Ethereum’s production network.
