Token Approval Risks & Revocation

Overview

Every time you interact with a DeFi protocol, you grant a token approval that can remain active indefinitely — giving the contract permission to spend your tokens without further consent. These unlimited approvals represent a major security risk: if the protocol is exploited or turns malicious, an attacker can drain every approved token from your wallet. Managing approvals is especially important for users active across multiple protocols on Ethereum and Layer-2 networks. Tools like Revoke.cash make it easy to audit and revoke stale permissions on a regular basis. For additional wallet security strategies, see our MetaMask setup guide and our best DeFi wallets comparison.

Key Takeaways

• Token approvals grant smart contracts permission to spend your tokens — often with unlimited allowance.
• If a protocol is exploited, the attacker can drain any token you've approved to that contract.
• Approvals persist even after you stop using a protocol — they don't expire.
• Revoking approvals costs a small gas fee but is essential for ongoing security.

Practical Tips

• Check and revoke approvals monthly using Revoke.cash (Ethereum + L2s) or bsccheck.com (BSC).
• Some wallets (Rabby) let you set limited approvals by default instead of unlimited.
• Before approving a new protocol, ask: 'Do I trust this contract with ALL of this token?'