What Are Smart Contract Vulnerabilities?

Smart contracts can fall prey to hacks due to a range of vulnerabilities. Here are some examples of smart contract vulnerabilities.

Marcel Deer
By Marcel Deer
Romi Hector
Edited by Romi Hector

Published May 30, 2022.

Smart contracts are as immutable, unchangeable, and secure. However, they are not without their flaws. As such, understanding smart contracts entails understanding their vulnerabilities as well.

Examples of Smart Contract Vulnerabilities

Just like any software, smart contracts are vulnerable to attack. The most common types of vulnerabilities include:

  • Error in calculating the output token amount This can happen when the underlying token price changes unexpectedly or there is an error in the smart contract code.
  • Reentrancy This is when a malicious contract calls itself multiple times to drain the target contract's resources.
  • Frontrunning This is when a contract observes another contract’s activity and executes a similar transaction before it. This can be used to exploit race conditions or take advantage of market conditions.
  • Dependency on execution order This can happen when the smart contract code depends on the order in which transactions are processed.
  • Arithmetic issues This can happen when two large integers are added or subtracted, resulting in an integer overflow.
  • Block gas limit vulnerabilities This can happen when the gas limit is not set properly, resulting in a Denial of Service (DoS) attack.
  • Timestamp dependence This can happen when the contract code uses the timestamp to make decisions. This can be exploited to manipulate the outcome of the contract.

These are just some of the most common smart contract vulnerabilities. It is important to note that these vulnerabilities can lead to the loss of funds and data or even the destruction of a smart contract. Therefore, it is crucial to be aware of these vulnerabilities and take steps to mitigate them when developing a smart contract.