DeFi Smart Contract Vulnerabilities Audit Guide

Here's a thinking process:

1. Analyze User Request:

   • Topic: DeFi smart contract vulnerabilities
   • Quantity: 3 common ones
   • Requirement: List them + how to detect them
   • Constraint: Be specific

2. Identify Key Vulnerabilities in DeFi Smart Contracts:
   I need to pick 3 of the most common, impactful, and well-documented vulnerabilities. Good candidates:

   • Reentrancy attacks
   • Integer overflow/underflow (though less common now with Solidity ^0.8.0, still relevant in older code or other languages)
   • Access control issues (ownership, admin privileges)
   • Front-running / MEV related issues
   • Flash loan attacks (often exploiting oracle manipulation or logic flaws)
   • Token approval / ERC20 allowance mishandling
   • Timestamp dependence
   • Unchecked return values