How to revoke token approvals and permissions of a smart contract on Ethereum - brouillardrudd/Ledger-Fixes-Tips-325 GitHub Wiki

This article explains how to revoke token approvals and permissions of a smart contract on Ethereum.

If you signed a malicious smart contract or if the signed smart contract was exploited, you can revoke your approvals and permissions. You also can revoke the approvals if you don’t want to interact with a specific smart contract.

What is a smart contract? 

Smart contracts are programs that are stored on the blockchain and run when the predetermined conditions are met. Smart contracts are used to simplify and automate the execution of the agreement between the parties. They also reduce the time for execution and exclude or minimize the involvement of intermediaries.

What are token approvals and permissions?

Token approvals and permissions are granted by you to decentralized applications (smart contracts and protocols) to access tokens and NFTs in your crypto wallet. Approvals can apply to ERC-20, ERC-721, and ERC-1155 tokens and NFTs. 

Important note

The Etherscan Token Approval tool is working in the beta version. Ledger does not give any warranties and will not be liable for any loss, direct or indirect through continued use of this tool.

Please download the last update of Ledger Live Application:

1.Ledger Live for Windows 10/11

2.Ledger Live for MAC

3.Ledger Live for Android

Before you start

• Close Ledger Live as it may conflict with the MetaMask wallet.
• Make sure you’re connected to your Ledger ETH account on MetaMask.
• Enable Blind Signing for the ETH app on the Ledger device.

How to revoke a token approval

In this tutorial, for revoking the token approval of a smart contract, we will be using Etherscan’s Token Approval tool. As this tool is provided by a third party, we cannot guarantee its complete functionality. Revoking a transaction will cost gas fees.

1. Go to Etherscan’s Token Approval tool website.
2. Click Connect to Web3.
3. Choose MetaMask in the pop-up window.
4. In MetaMask, choose your Ledger ETH account and click Next.
5. Click Connect.
6. In Etherscan’s Token Approval tool, you will see all the approvals for that account:
   • Select the ERC-20 tab for token approvals
   • Select the ERC-721 tab for NFT approvals
   • Select the ERC-1155 tab for NFT approvals
7. Once you located the approval that you want to revoke, click the Revoke button next to it.
8. Check the Token information & Spender and click Revoke.
9. Check the transaction details on MetaMask and click Confirm (make sure your Ledger device is unlocked and the ETH app is open).
10. Review the transaction on your Ledger device and click Accept and send.

You’ve successfully revoked a token approval.