Approvals & Revoke Tools

To use your web3 wallet with DeFi protocols you must approve smart contracts for each token you want to stake, swap, or use in a liquidity pool. Every protocol has smart contracts you must approve and every contract approval costs gas. Learn More: What Are Token Approvals?, Revoke Cash

Sometimes a site will ask you to "sign" a transaction, this type of interaction does not cost gas and serves as way to prove ownership or control of the wallet you're connecting with. On the user end, these are all simple clicks. Learn More: What are Permit Signatures?, RevokeCash

Some contracts will approve a set amount of tokens, others will be "infinite approvals", approving unlimited access until revoked; infinite approvals increase vulnerability to risk. 

Every contract you approve, remains approved until revoked. 

A contract exploit is when code is compromised by an existing loophole or glitch.  Warning signs for unsafe contracts include unlocked liquidity, unlimited mint functions, and other transparent issues in the code. Smart contract security audits will show a detailed analysis of these functions and are often publicly available. 

Quick Tips:

1. Use multiple wallets. Separate wallets addresses that hold funds from wallet addresses interacting with smart contracts. Start fresh wallets & move funds if there is any concern.
2. Revoke approvals and avoid smart contract interactions with unreliable protocols. 
3. Use Revoke Tools to easily revoke contract approvals.
4. Use a hardware wallet like Trezor or Ledger to increase security.

Learn More:

• What Are Smart Contracts & How They Work, Investopedia  
• What is Smart Contract Risk?, Coinmarketcap Alexandria

Hardware wallets like Trezor and Ledger¹ increase security when interacting with smart contracts by putting private keys on a physical device, this protects you from unauthorized transactions taking place as you navigate through smart contracts. Without access to your seed phrase, a malicious actor would need to gain access to your physical device.

If you approve a malicious contract, a hardware wallet will not stop the approval.

Trezor and Ledger are both compatible with your EVM wallet.

Learn more: 

• What is a Hardware Wallet?, Trezor
• Hardware Wallets And MetaMask: Best Security Combo, Consensys

¹Trezors, Ledgers and all hardware wallets should be purchased from the official websites only. Never buy a hardware wallet from a third party like Amazon or Best Buy, it is safest to always double check the URL and purchase from the original manufacturer.