--- title: "Ethereum Delays Glamsterdam Upgrade on Hoodi Testnet Over Smart Contract Vulnerabilities" description: "Core developers postponed the Oct. 26 activation after auditors found that gas pricing changes would break invariants relied upon by certain projects." url: https://basisdesk.news/analysis/ethereum-delays-glamsterdam-upgrade-hoodi published: 2026-11-06T14:02:14.364Z modified: 2026-11-06T14:02:14.364Z section: Tech & Protocols author: Basis Desk Newsroom (AI-generated, source-verified) sentiment: neutral tickers: [ETH] tags: [Ethereum, Glamsterdam, Hoodi, Smart Contracts, Gas Pricing] license: Quote with attribution to Basis Desk (basisdesk.news). Not financial advice. --- # Ethereum Delays Glamsterdam Upgrade on Hoodi Testnet Over Smart Contract Vulnerabilities Core developers postponed the Oct. 26 activation after auditors found that gas pricing changes would break invariants relied upon by certain projects. ## At a glance - **What happened:** Ethereum core developers delayed the Glamsterdam upgrade on the Hoodi testnet, which was scheduled for Oct. 26. - **Why it matters:** The upgrade's gas pricing changes break invariants relied upon by certain smart contracts, exposing them to potential vulnerabilities. - **Who is affected:** Ethereum developers, Hoodi testnet node operators, and smart contract creators. - **What's next:** A new activation schedule for the Hoodi testnet will be announced at a later date. - **Primary source:** [EIP-8037/EIP-8038 Glamsterdam](https://blog.ethereum.org/en/2026/11/06/glamsterdam-8037-8038) — Ethereum Foundation Blog ## Key points - Ethereum delayed the Glamsterdam upgrade on Hoodi after auditors found gas pricing changes would break smart contract invariants. - The Oct. 26 activation at epoch 132,352 has been canceled, and no new date has been set. - Node operators must update their software to versions that do not include the scheduled Hoodi activation. ## Editorial remark - **Context:** The delay highlights the complex interactions between Ethereum's L1 scaling roadmap and existing smart contracts, particularly when gas pricing models change. - **Impact:** Node operators on Hoodi must update their clients to avoid splitting off the network. Application developers must verify if their contracts are vulnerable to the invariant changes. - **Watch:** A new activation schedule for Hoodi will be announced once core developers resolve the smart contract vulnerability issues. Ethereum core developers have canceled the scheduled activation of the Glamsterdam upgrade on the Hoodi testnet, which was previously slated for Oct. 26, 2026. The delay follows findings that the upgrade's changes to gas pricing would break invariants relied upon by some smart contracts, exposing them to vulnerabilities [1]. ## Vulnerabilities Discovered by Chainsecurity The delay stems from issues identified by Chainsecurity, which found that certain projects rely on invariants that are broken by EIP-8037 and EIP-8038 [1]. These EIPs rework how gas is charged for state creation and access operations [1]. Based on the discoveries, the All Core Developers (ACD) group decided to postpone the Hoodi hardfork until a resolution can be reached [1]. To facilitate a pragmatic decision, the Ethereum Foundation is engaging multiple auditing firms and conducting internal reviews [1]. A public repository detailing the eight broken invariants has been created to help contract developers verify if their projects are affected [1]. ## Hoodi Configuration Reverted The previously scheduled activation on Hoodi at epoch 132,352 is no longer planned, and a replacement date has not been set [2]. Core developers decided on ACDE #248 to delay the upgrade to allow for further investigation into how EIP-8037 interacts with mainnet smart contracts [2]. This delay removes both the Amsterdam execution layer activation and the Gloas consensus layer activation, as well as a gas-limit schedule that would have raised Hoodi's gas limit to 200M [2]. Node and validator operators are advised to update their clients to software versions that reflect the postponed activation [2]. ## Glamsterdam Upgrade Details Glamsterdam is a major upgrade that combines the Amsterdam execution layer and the Gloas consensus layer [3]. Its primary features are enshrined proposer-builder separation (ePBS) under EIP-7732 and block-level access lists (BALs) under EIP-7928 [3]. ePBS aims to reduce reliance on trusted middleware by bringing the separation of block proposers and builders into the consensus protocol [3]. BALs are designed to allow clients to parallelize state reading and transaction validation, improving efficiency [3]. In addition to these changes, the upgrade includes significant adjustments to gas accounting. EIP-8037 increases the cost of creating state, while EIP-8038 updates the cost of state access [3]. Other changes cover intrinsic transaction gas, calldata, and block gas accounting [3]. Application developers have been advised to test their contracts against these new rules, especially those relying on fixed gas stipends or assumptions about remaining gas [3]. ## Client Software Updates Several client teams have released updates to unschedule the Hoodi fork. For example, Besu released version 26.10.1, which reverts the scheduling of Amsterdam on Hoodi [6]. The eth-clients/hoodi repository removed `amsterdamTime` from Hoodi's genesis file, moving the `GLOAS_FORK_EPOCH` to infinity [7]. Lodestar and ethrex also merged pull requests to align with the unscheduled activation [7]. Developers using external block-building infrastructure must follow instructions from their tooling providers [2]. ## Sources 1. [EIP-8037/EIP-8038 Glamsterdam](https://blog.ethereum.org/en/2026/11/06/glamsterdam-8037-8038) — Ethereum Foundation Blog, 2026-11-06 2. [Glamsterdam on Hoodi Postponed](https://blog.ethereum.org/en/2026/10/22/glamsterdam-hoodi-delay) — Ethereum Foundation Blog, 2026-10-22 3. [Glamsterdam Hoodi Testnet Announcement](https://blog.ethereum.org/en/2026/10/16/glamsterdam-hoodi-announcement) — Ethereum Foundation Blog, 2026-10-16 4. [Glamsterdam Testnet Announcement](https://blog.ethereum.org/en/2026/09/17/glamsterdam-testnet-announcement) — Ethereum Foundation Blog, 2026-09-28 5. [Ethereum Developers Cancel Oct. 26 Glamsterdam Upgrade on Hoodi](https://thedefiant.io/news/blockchains/ethereum-developers-cancel-oct-26-glamsterdam-upgrade-on-hoodi) — thedefiant.io, 2026-10-22 6. [Unschedule Amsterdam on Hoodi by daniellehrner · Pull Request #11709 · besu-eth/besu](https://github.com/besu-eth/besu/pull/11709) — github.com, 2026-10-22 7. [chore: unschedule Hoodi Glamsterdam activation by barnabasbusa · Pull Request #33 · eth-clients/hoodi](https://github.com/eth-clients/hoodi/pull/33) — github.com, 2026-10-22 8. [Alpenglow: What We Learned Running Solana's Biggest Consensus Change](https://www.galaxy.com/insights/perspectives/alpenglow-what-we-learned-running-solanas-biggest-consensus-change) — galaxy.com, 2026-10-20 --- Basis Desk Newsroom · AI-generated, source-verified · https://basisdesk.news/about/how-we-use-ai