Arbitrum temporarily blocks new smart contract deployments to mitigate emerging security threats

Arbitrum's Security Council halted the activation of new Stylus contracts on Arbitrum One and Nova beginning October 2, 2026, in response to sophisticated AI-assisted attacks targeting the WebAssembly-based programming environment. The pause was implemented by raising activation gas costs to prohibitive levels without requiring a software upgrade, while existing contracts remain operational. The restriction stays in effect pending future decisions from the Arbitrum Foundation and ArbitrumDAO on when to reopen the feature.

Stylus represents Arbitrum's experimental programming layer built on WebAssembly technology, enabling developers to write smart contracts in languages beyond Solidity. The October pause prevents newly written or updated programs from becoming active, though code storage and existing running contracts remain unaffected. The Security Council identified vulnerabilities exploitable through AI-driven attack methods targeting the WebAssembly environment's unique architecture.

The implementation demonstrates how blockchain networks can respond to security risks without requiring software upgrades—by adjusting economic incentives through gas pricing rather than altering core protocol rules. Developers with expiring Stylus contracts can still extend their validity using automated renewal processes, preserving operational continuity for established applications while blocking new entry points.