Ethereum pulls Glamsterdam’s Hoodi test over contract risk

Ethereum core developers postponed Glamsterdam’s planned October 26 activation on the Hoodi test network to investigate how its gas changes could affect existing smart contracts. The Ethereum Foundation’s postponement notice says there is no replacement date; the change also removes a planned increase to Hoodi’s gas limit to 200 million.

The concern centers on EIP-8037, which changes the gas cost of creating new blockchain state, and its interaction with existing contracts. Gas is the unit used to meter computation and data operations. A contract can call another contract, check whether that call succeeded, then decide whether to continue, retry or record a failure. Those steps depend in part on how much gas remains.

How could the new gas rules affect an old contract?

EIP-8037 separately meters the cost of creating state, such as a new storage slot. The Ethereum Foundation’s repricing guide says the change is meant to make gas costs better reflect the resources those operations use. Glamsterdam also includes EIP-8038, which updates state-access costs.

Security researchers warned that changing these costs can shift how much gas a contract has left after a failed call. Some contracts rely on a gas allowance being exhausted so that failure-handling code also runs out of gas and the whole transaction reverts. If the new accounting leaves enough gas for that code to finish, the contract could record a failure or disable a retry where the old rules would have rolled everything back.

Think of a contract’s remaining gas as the balance left in a prepaid account: changing the price of one operation changes what the balance can still cover. The analogy stops there; the risk comes from the contract’s precise execution rules and the proposed accounting changes.

What was removed from the Hoodi schedule?

The postponement cancels both the Amsterdam execution-layer and Gloas consensus-layer activations set for October 26 at 17:42:48 UTC, as well as the scheduled gas-limit increase. Hoodi is a public test network used to rehearse protocol changes. Glamsterdam had already activated on Sepolia on October 6, but that did not set a mainnet date.

The Foundation says the update changes Hoodi’s future upgrade configuration, not its recorded chain history. Hoodi node and validator operators are told to check both execution- and consensus-layer client instructions so their software no longer schedules the cancelled activation.

Does the delay mean mainnet contracts are being exploited?

No confirmed exploitation is reported in the sources. The issue is how deployed contracts might behave under proposed rules, not a change to Ethereum mainnet’s current rules. The Foundation says the investigation concerns EIP-8037’s interaction with mainnet smart contracts; it has not announced a new Hoodi date or a mainnet activation date.

Source material

• postponement notice — blog.ethereum.org
• repricing guide — blog.ethereum.org