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Smart Contract Reentrancy Attack Lab


The DAO (Decentralized Autonomous Organization) attack was one of the major hacks that occurred in the early development of Ethereum. At the time, the contract held over $150 million. Reentrancy played a major role in the attack, which ultimately led to the hard fork that created Ethereum Classic (ETC). As of 2022, the reentrancy attack is still a common attack on Ethereum.

The purpose of this lab is to give students a hands-on experience on the reentrancy attack. Students are given two smart contracts, a vulnerable one (the victim contract) and an attack contract. Students will go through the entire attack process to see how exactly the attack works. They will see in person how such an attack can steal all the money inside the victim contract. The attack will be conducted on the SEED emulator, with an Ethereum blockchain deployed inside.

Tasks (PDF)

Time (Suggested)

  • Supervised (closely-guided lab session): 2 hours
  • Unsupervised (take-home project): 1 week

Open Source

The SEED Labs project is open source. If you are interested in contributing to this project, please check out our Github page: https://github.com/seed-labs/seed-labs.