codeesura/Ethereum-Smart-Contract-and-Attack-Simulation

This repo contains two Ethereum smart contracts, KurbanContract and Attack, exemplifying a reentrancy attack. The KurbanContract manages user balances, while Attack exploits a vulnerability, serving as a vital educational resource in smart contract security.

Ethereum Smart Contract Attack Simulation

This repo contains two Ethereum smart contracts, KurbanContract and Attack, exemplifying a reentrancy attack. The KurbanContract manages user balances, while Attack exploits a vulnerability, serving as a vital educational resource in smart contract security.

KurbanContract

KurbanContract is a simple Ethereum smart contract that allows users to deposit Ether, check their balance, and withdraw their funds. It uses a mapping balances to keep track of the amount of Ether each user has deposited into the contract.

Functions in KurbanContract:

• deposit(): A payable function that allows users to deposit Ether into the contract. The deposited amount is added to the user's balance.

• getBalance(): A function to view the total balance of the contract.

• withdraw(): A function that allows users to withdraw their deposited Ether from the contract. If successful, the balance of the user is set to 0.

Attack

Attack is a malicious Ethereum smart contract that exploits the reentrancy vulnerability in KurbanContract. It uses the fallback function to recursively call the withdraw function of KurbanContract, draining the contract of all its Ether.

Functions in Attack:

• getBalance(): A function to view the total balance of the contract.

• attack(): A payable function that deposits Ether into KurbanContract and then immediately calls withdraw to start the attack.

• fallback(): A payable function that automatically gets executed if no other function matches the given function signature. In this case, it recursively calls KurbanContract's withdraw function if the balance of KurbanContract is greater than or equal to the amount of Ether sent with the function call.

• receive(): An external payable function that allows the contract to receive Ether.

To initiate the attack, the attack() function needs to be called with a certain amount of Ether. Once started, the attack will continue until KurbanContract has been drained of all its Ether.

Note: This code is for educational purposes only and should not be used in production as it contains a well-known reentrancy vulnerability. Always follow best practices when writing Ethereum smart contracts.

Disclaimer

This repository and its code are intended for educational purposes only. Misuse of this code can result in loss of funds or potential legal repercussions. Always be aware of the security concerns and never use untested code in a production environment.