ENS Registry Migration: Bug Fix, New Features – The Ethereum Name Service

Today we’re announcing we’re working with the ENS root key holders to replace the ENS registry contract. This fixes an unexploited bug as well as adds some new functionality.

No immediate action is required for most users. All names are safe, and if you’re an average user you can continue using ENS as normal.

Wallets, dapps, subdomain registrars, libraries, and any other services that use ENS need to upgrade to the new registry contract. In the meantime, services using the old registry contract will still function, though they will soon start to return stale results. We recommend all services upgrade right away.

Here’s a guide explaining exactly what these services need to do: Guide for DApp Developers

We were recently made aware of some unexpected behavior of the current ENS registry contract. We will be posting a full post-mortem at a later date.

In short, if a person transferred an ENS name in a specific way, they would be capable of later claiming it back away from the new owner. This would not have worked if a person transferred a name in the normal way. In other words, to make use of this bug, the person doing the transferring had to have been intentionally setting themselves up from the beginning to claim it back.

As far as we can tell, this has never been exploited. This new registry contract removes the possibility.

We’re taking advantage of this upgrade to introduce some new functionality to streamline ENS. New features include the abilities to:

• Configure the owner and resolver of a name in a single transaction
• Create a subdomain and set a resolver for it in a single transaction
• Authorize contracts or other accounts to make changes to domains (change their resolver and owner) on their behalf, similar to ERC721’s ‘authorization’ functionality