Ethereum’s only hard fork happened because of a reentrancy attack.

When the first DAO was launched in 2016, it held 14% of the entire Ethereum value.

Today, 4 out of 20+ hacks in 2023 have been reentrancy attacks.

What are they and how to prevent them? 👇 1/ What is a reentrancy attack?

When a hacker "reenters" a function to do something malicious.

A hacker typically exploits a callback function (like a “fallback” function or “onERC721Received’) to maliciously "reenter" the victim’s contract and execute a malicious transaction.

In 2022, DeFi protocols lost $403.2 million in 40+ oracle manipulation attacks.

Oracle manipulations are one of the most common attacks in crypto.

But what are they and how do they happen? 👇 1/ 📃 First, what is an oracle?

An oracle bridges blockchains to external systems (like APIs or other off/on-chain data).

They enable smart contracts to execute actions based upon inputs and outputs from the real world.

In 2022, DeFi protocols lost $403.2 million in 40+ oracle manipulation attacks.

Oracle manipulations are one of the most common attacks in crypto.

But what are they and how do they happen? 👇 📃 First, what is an oracle?

An oracle bridges blockchains to external systems (like APIs or other off/on-chain data).

They enable smart contracts to execute actions based upon inputs and outputs from the real world.