Ethereum Layer 2 network Optimism network has reverted the network to a permissioned state to avoid instabilities until vulnerabilities discovered during third-party audits are patched.

OP Labs, the software development company behind Optimism, proposed a protocol upgrade called “Granite” which includes set of smart contract upgrades to fix the vulnerabilities identified in the audits and a layer 2 hard fork to improve the performance of its fault proof system.

Optimism’s fault proof system, which allows users to contest incorrect or fraudulent transactions, went live on the mainnet in June. The permissionless fraud proof system allows anyone, not just trusted proposers, to participate in the fraud detection process and was considered a step towards better decentralization.

OP Labs said that none of the vulnerabilities identified had ever been exploited, and emphasized that user assets were never in danger of being compromised.

“While the auditors did discover some high severity issues, no user assets were ever at risk,” said Mofi Taiwo, a protocol engineer at OP Labs, in the proposal.

If the community votes to pass the proposal, the Granite upgrade will be executed on Sept. 10 at 16:00:01 UTC. OP Labs said it does not anticipate any downtime due to the upgrade, but advised all node operators to upgrade before Sept. 11 to avoid a chain split.

Most Optimism governance delegates were in favor of moving the proposal forward to a vote, while some raised concerns about executing a hard fork that has not been audited.

“Such an upgrade shouldn’t pass without an audit, as it is already a fix of existing bugs. If there are further bugs introduced in this upgrade, it will result in irreparable harm to the chain which will require further fixes,” wrote a user called Takeshi on the governance forum.