Glamsterdam Hoodi delay pushes Ethereum upgrade timeline back

The Glamsterdam Hoodi delay means Ethereum's next major upgrade has lost its final public rehearsal date. The Ethereum Foundation said on Thursday, Oct. 22, that the Glamsterdam fork on the Hoodi test network, set for Oct. 26 at 17:42:48 UTC, has been postponed and that no new activation date has been chosen.

What happened

Core developers made the call on the All Core Devs Execution call, number 248, to investigate how EIP-8037 interacts with smart contracts already running on mainnet, the foundation said. The change also removes the plan to lift Hoodi's gas limit to 200 million at the same epoch. Hoodi's chain history is not affected.

The concern came from ChainSecurity. In an analysis published on Oct. 13, the security firm showed that EIP-8037, which reprices the creation of new state to slow database growth, together with EIP-8038, could change how contracts behave when a call they make runs out of gas, CoinDesk reported.

Some contracts are written to catch a failed call and carry on, for example by recording that an attempt failed. Developers sometimes rely on there being too little gas left for that step, so the whole transaction reverts. Under the new rules, refunded gas could let such a handler finish, turning a temporary failure into a permanent one. Cointelegraph gave an example: an affected contract could delete a user's claim or block a retry, even though the operation itself was valid.

Why it matters

The risk also runs the other way. By ChainSecurity's math, a fresh storage slot could cost 110,020 gas after a separate allowance runs out, compared with 22,100 today, CoinDesk reported. A contract with a fixed gas budget could then fail during an otherwise valid operation.

ChainSecurity said on Thursday that it had found "13 real-world examples" and was in responsible disclosure with the projects involved, Decrypt reported, without naming them. CoinDesk stressed that the firm has not shown that a major live protocol is exploitable. Security researcher pcaversaccio called the risks "serious" in an Oct. 21 GitHub comment, Cointelegraph said. The foundation told application developers and mainnet users not to plan Hoodi testing around an Oct. 26 activation.

Timing is the market issue. Glamsterdam went live on Sepolia on Oct. 6 and began producing blocks with room for almost 200 million gas, over triple the 60 million mainnet allows, according to Decrypt, as we covered in the Sepolia test, and developers had been weighing an early-December mainnet date, Cointelegraph said. The Glamsterdam Hoodi delay makes that harder to hit, since a mainnet schedule was to follow successful Hoodi testing.

What's next

Glamsterdam brings a new way of selecting block builders and changes meant to let the network handle larger blocks. No decision on the two gas proposals has been announced. The foundation's research teams have been busy on other fronts too, including the zkAPI launch.

Node and validator operators should run the client releases listed as incorporating the postponement, according to the Ethereum Foundation post. A revised schedule will be announced separately, and the Glamsterdam Hoodi delay leaves the year-end mainnet goal Decrypt described in doubt.