DeFi Smart Contract Vulnerabilities Audit Guide

Here are three of the most common DeFi smart contract vulnerabilities, along with specific detection methods for each:

1. Reentrancy

Vulnerability Description:
Reentrancy occurs when a smart contract calls an external contract (e.g., a token contract’s transfer function) before updating its own internal state. A malicious external contract can then re-enter the vulnerable function multiple times before the initial call completes, allowing an attacker to drain funds or manipulate state.

Specific Detection Methods:

• Static Analysis with Control Flow Graphs (CFG):
  • Identify all external calls (e.g., call, delegatecall, transfer, transferFrom).
  • Check if any state-changing operations (e.g., balances[user] -= amount) occur after the external call in the same function.

  
  
  

  • Tools: Slither, Mythril, or SARIF-based analyzers.