Arbitrum Halts New Stylus Activations Over Chain Liveness Concerns
Arbitrum has temporarily halted new Stylus contract activations on its Arbitrum One and Arbitrum Nova networks following a security action taken by its Security Council on October 2. The measure targets hand-crafted WebAssembly (WASM) programs that could disrupt chain operations, though no user funds have been at risk so far.
The pause specifically blocks the activation step required to make Stylus contracts executable, meaning developers cannot deploy or reactivate expired contracts until the freeze is lifted. Existing contracts remain operational until their expiration, which typically lasts 365 days. Regular Solidity and EVM contract activity continues unaffected.
The Security Council raised the Stylus activation gas requirement to an impractical level to enforce the pause, a change that did not require an upgrade to the network’s operating software, ArbOS. The Arbitrum Foundation reassured users that it remains confident in Stylus and plans to reopen activations while addressing risks tied to hand-crafted WASM programs.
The emergency action also introduced a safeguard for BoLD’s one-step proofs on Arbitrum One, which could delay unconfirmed withdrawals if contradictory proofs are accepted. Transactions would continue processing normally during any such suspension. The ArbOS 61 upgrade had already renewed all active Stylus contracts on Arbitrum One, ensuring none will expire before August 20, 2027.
The Arbitrum Foundation will work with ArbitrumDAO to determine when and how activations resume, though no timeline has been set. This latest security measure follows other incidents, including a $24 million exploit on the AFX Trade bridge in July and a $71 million freeze linked to the KelpDAO attacker in April.