DeFi Smart Contract Vulnerabilities Audit Guide

Here are three of the most common and critical DeFi smart contract vulnerabilities, along with specific methods to detect them.

1. Reentrancy Attacks

Description:
Reentrancy occurs when a smart contract makes an external call to an unknown or untrusted contract before completing its state changes. The external contract can then re-enter the original contract’s function before the state is fully updated, allowing an attacker to drain funds or manipulate state logic.

Specific Detection Methods:

• Static Analysis with Slither/Oyente: Use tools like Slither (by Trail of Bits) or Oyente to scan for functions that perform external calls (call, delegatecall, staticcall) before modifying state variables. Slither specifically flags reentrancy-eth and reentrancy-no-eth warnings.
• Control-Flow Graph (CFG) Analysis: Manually or via tooling, analyze the control-flow graph to