Arbitrum Pauses New Stylus Activations Over Attack Threat

Arbitrum paused new Stylus contract activations on Arbitrum One and Nova to address a threat involving programs built outside the standard compiler toolchain. The emergency measure was taken around 11:30 a.m. ET (15:30 UTC) Friday, Oct. 2.

The pause blocks activation of new Stylus contracts, including application updates that require activation. Stylus applications already activated can continue running, while Solidity contract deployment and execution remain unaffected.

The measure addresses a threat involving WebAssembly programs built outside the standard Stylus compiler toolchain. The stated concerns are reduced on-chain activity and denial-of-service attacks, with no risk to user funds identified.

The measure is temporary.