Auditing Your Own Wallet's Token Approvals

Detailed Instructions

Begin by aggregating your approval data from the blockchain. Manually checking each transaction is impractical, so leverage dedicated approval-checking platforms. For Ethereum and EVM-compatible chains (like Polygon, Arbitrum), visit Etherscan's Token Approvals tool or use a service like Revoke.cash or Unrekt.net. Connect your wallet securely via WalletConnect. These tools scan the blockchain and present a list of all ERC-20 token approvals, including the spender contract address, the token symbol, and the approved amount (which may be infinite).

• Sub-step 1: Navigate to a tool like revoke.cash and connect your wallet.
• Sub-step 2: Review the list, paying special attention to approvals with an infinite amount (displayed as a very large number like 115792089...).
• Sub-step 3: Export or note down the spender addresses and token contracts for any suspicious or unused approvals.

Tip: Always use the official links for these tools to avoid phishing sites. Bookmark them for regular checks.

Detailed Instructions

Not all approvals are dangerous, but each represents a potential attack vector. Your goal is to perform a risk assessment on every spender contract. First, verify the legitimacy of the dApp. Check if you recognize and actively use the application. For unknown contracts, investigate them using a block explorer. On Etherscan, paste the spender address to view its contract source code, creator, and transaction history. Look for verification ticks and user comments. A high-risk indicator is an approval for a contract you no longer interact with or one created by an unverified, anonymous deployer.

• Sub-step 1: For each approval, search the spender address on a block explorer.
• Sub-step 2: Check the 'Contract' tab to see if the code is verified and review its functions.
• Sub-step 3: Assess the approved amount; infinite approvals to obscure contracts are the highest priority to revoke.

Tip: Use a spreadsheet to track your analysis, noting the contract, last use date, and your risk rating (High, Medium, Low).

Detailed Instructions

Revoking an approval sets your allowed spending limit for a specific token and contract back to zero. This is done by sending a transaction to the token's contract. You can execute this manually via a block explorer's 'Write Contract' feature or use the revoke tools from Step 1 for a simpler interface. The critical parameter is the spender address you wish to revoke. You will need to pay a gas fee for this on-chain transaction. For an infinite USDC approval to a suspicious contract 0x742d35Cc6634C0532925a3b844Bc9e, you would call the approve function on the USDC contract with a _spender of that address and a _value of 0.

• Sub-step 1: In your revoke tool, find the risky approval and click 'Revoke' or 'Update'.
• Sub-step 2: In the transaction prompt, confirm you are setting the new allowance to 0.
• Sub-step 3: Sign and pay for the transaction in your wallet. Wait for confirmation on-chain.

Tip: To revoke manually via Etherscan, find the token contract, go to 'Write Contract', connect your wallet, and call approve(spenderAddress, 0).

Detailed Instructions

Proactive security management is key to preventing future vulnerabilities. First, adopt the practice of using finite approvals instead of infinite ones whenever a dApp allows it. When you sign a transaction, it may ask you to approve a specific spending cap; choose a reasonable limit for your immediate needs. Second, make wallet approval audits a regular routine, perhaps monthly. Third, consider using a dedicated hot wallet for interacting with new or experimental dApps, keeping the majority of your assets in a separate, less-exposed wallet. You can also use wallet alert services or blockchain security platforms that monitor for suspicious approvals.

• Sub-step 1: When transacting, manually edit approval amounts in your wallet pop-up before signing.
• Sub-step 2: Schedule a recurring calendar reminder to repeat Steps 1-3 of this audit.
• Sub-step 3: Research and enable security features in your wallet, like transaction simulation or blocking malicious sites.

Tip: For advanced users, interacting with contracts via a smart contract wallet (like Safe) can provide multi-signature controls and more granular permission settings.

Detailed Instructions

Begin by using a blockchain explorer like Etherscan for Ethereum or Polygonscan for Polygon. Navigate to the 'Token Approvals' section under your wallet address. For a more comprehensive and user-friendly analysis, employ dedicated security platforms such as Revoke.cash, Etherscan's Token Approval Checker, or DeBank. These tools aggregate approvals across multiple chains. The key is to generate a full inventory.

• Sub-step 1: Connect your wallet to a trusted approval-checking website. Ensure you are on the correct domain to avoid phishing.
• Sub-step 2: Select the network you wish to audit (e.g., Ethereum Mainnet, Arbitrum, BNB Chain). You must repeat this for every network you use.
• Sub-step 3: Review the generated list, which will show the token (like USDC, WETH), the approved spender contract address, and the approved amount (often an astronomically high uint256 value).

Tip: Bookmark the legitimate URLs for these tools (e.g., https://revoke.cash) to avoid fake sites. This step is purely investigative and involves no on-chain transactions.

Detailed Instructions

Not all approvals are dangerous. Your goal is to distinguish between active, necessary approvals for protocols you currently use and dormant, excessive, or suspicious approvals. An approval with an infinite amount (115792089...) to an obscure contract is high-risk. Assess each entry based on:

• Sub-step 1: Check the spender contract. Research the contract address. Is it a well-known, audited DeFi protocol like Uniswap V3 (0xE592427A0AEce92De3Edee1F18E0157C05861564) or a random, unverified address?
• Sub-step 2: Evaluate the approval amount. An approval for a specific, small amount (e.g., 100 USDC) is less risky than an unlimited approval. The standard infinite approval looks like 115792089237316195423570985008687907853269984665640564039457584007913129639935.
• Sub-step 3: Recall your usage. Have you interacted with this dApp in the last month? If not, the approval is likely dormant. Prioritize revoking approvals for abandoned projects, unknown contracts, and any approvals you don't explicitly remember making.

Tip: High-value wallets should prioritize revoking unlimited approvals first, as they present the greatest potential loss if the spender contract is compromised.

Detailed Instructions

Revocation is performed by calling the approve function on the token's contract, setting the spender's new allowance to zero. You can do this directly via a block explorer or through your wallet connected to a revocation tool. Always verify gas fees and contract details before confirming.

• Sub-step 1: Using Revoke.cash, select the approval you wish to revoke and click 'Revoke'. The tool will pre-populate a transaction setting the allowance to 0.
• Sub-step 2: Using a block explorer manually, go to the token contract (e.g., USDC: 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48), connect your wallet, and find the approve function. Enter the spender address and set the amount to 0.

codeCopy
// The approve function call structure
approve(address spender, uint256 amount)
// Example: Revoke USDC for spender 0x1234...
spender: 0x1234567890123456789012345678901234567890
amount: 0

• Sub-step 3: Confirm the transaction in your wallet. Pay the network gas fee. Wait for confirmation.

Tip: Consider setting a custom, low gas limit (e.g., 50,000) for ERC-20 approve revocations to prevent being caught by a malicious contract's fallback function, though most tools handle this safely.

Detailed Instructions

Post-revocation, change your interaction habits to maintain a minimal approval footprint. The principle is to grant only what is needed, for as short a time as possible. Use emerging wallet features and standards designed for safety.

• Sub-step 1: Use 'Permit' signatures where available. Some dApps support EIP-2612 permit, which allows token approval via a signature instead of a transaction, often for a specific amount and expiry time.
• Sub-step 2: Leverage wallet allowance managers. Wallets like Rabby have built-in features that warn you about infinite approvals and allow easy management. Browser extensions like Fire (Revoke Cash companion) can monitor new approvals in real-time.
• Sub-step 3: Adopt specific, expiring approvals. When interacting with a new protocol, if given the option, manually set a spending cap (e.g., $500 worth of tokens instead of infinite) and be mindful. Some advanced users interact directly with contracts to include an expiry timestamp, though this is not yet a universal standard.

Tip: Make auditing approvals a regular part of your security hygiene, perhaps on a monthly or quarterly schedule, especially after intensive DeFi activity. Treat approvals as temporary permissions, not permanent grants.