A smart contract vulnerability refers to weaknesses or flaws in the code of a smart contract that can be exploited by malicious actors. Smart contracts are self-executing contracts with the agreement directly written into code and run on a blockchain. However, if there are coding errors or oversights, they can lead to unintended behavior.Common vulnerabilities include reentrancy attacks, where an attacker repeatedly calls a function before the initial call is completed, and integer overflow/underflow, which can cause values to exceed their intended range. These vulnerabilities can result in significant financial losses or unauthorized access to assets.Proper testing, code reviews, and audits are essential in preventing these vulnerabilities. Once deployed, smart contracts are often immutable, meaning that fixing a bug can be challenging. As the use of smart contracts grows, awareness and understanding of potential vulnerabilities become crucial for anyone involved in developing or using these programs.