Arbitrum Stylus pause: ArbitrumDAO now holds the keys to the restart
The Security Council froze new Stylus activations on Arbitrum One and Nova, and the decision on when to lift the freeze now sits with ArbitrumDAO.
Arbitrum’s Security Council has paused new Stylus activations on Arbitrum One and Nova in an emergency action, and it handed the decision on when to lift the freeze to ArbitrumDAO. The Council said in its action report on October 2, 2026, that the Arbitrum Foundation will work with ArbitrumDAO to determine the timeline and manner of restoring activations, with no restart date given.
The move, executed onchain around 15:30 UTC, was a unilateral emergency exercise of the Council’s own powers: a small body freezing a developer platform on two production chains, then passing the restart decision to the wider DAO. That sequencing makes the resumption a live test of Arbitrum’s governance, where a security authority with emergency powers must negotiate the pace of a rollback with token holders.
The freeze itself was implemented without a network upgrade. The Council said it raised the activation gas requirement for new Stylus programs to a prohibitively expensive level, a configuration change that requires no ArbOS upgrade. Existing Stylus contracts keep executing and can renew their lifetimes through the permissionless keepalive mechanism, and ordinary Solidity deployments are unaffected, according to the official developer notice. Reactivating an expired program, or one that needs reactivation after a Stylus version change, is also blocked.
Why the Council acted
Arbitrum attributed the pause to increasingly sophisticated AI-assisted attacks involving hand-crafted WebAssembly (WASM) programs outside the standard Stylus compiler toolchain. The Council said the known bugs threaten chain liveness, including denial-of-service risk, and that no attack permitting theft of user funds has been discovered.
The same emergency action added a permissionless guard on the BoLD one-step proof on Arbitrum One. If the proof accepts two conflicting answers to the same step of an open challenge, Arbitrum One’s settlement to Ethereum is put on hold. In that case, unconfirmed messages from One to Ethereum, including withdrawals, would be delayed until the Council deploys a fix and resumes settlement. The guard does not itself pause withdrawals.
The Foundation framed the emergency action as part of an ongoing series of proactive security measures. No date has been set for ArbitrumDAO to take up the restart question.
