DeFi Smart Contract Vulnerabilities Audit Guide

Here are three common DeFi smart contract vulnerabilities, along with specific detection methods and mitigation strategies. These are based on industry-standard security practices (e.g., from OWASP Smart Contract Top 10, Slither, and real-world exploit post-mortems).

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1. Reentrancy Vulnerability

What it is:

An attacker recursively calls a vulnerable function before its first execution completes, allowing them to drain funds or manipulate state variables multiple times. This typically occurs when a contract sends external calls (e.g., transfer()) before updating internal state (e.g., balances[msg.sender]).

Detection Methods:

• Static Analysis Tools:
  • Use Slither with the reentrancy-eth detector. It flags functions that make external calls before state changes.
  • Use Mythril or Halmos for symbolic execution to find reentrancy paths.
• **Manual Code Review