Here are a few bug patterns you should be always looking out for:

Lack of Input Validation: This occurs when a function does not properly check the inputs it receives, potentially allowing for unexpected behavior or manipulation. Ensuring all inputs are validated against expected types, ranges, or formats is critical to prevent exploits.

Incorrect Storage Updates: Smart contracts store data in variables that represent state. If the contract logic incorrectly updates these variables, it could lead to inconsistent states or vulnerabilities. Auditors must meticulously trace how state variables are modified to ensure they align with the intended logic.

Rounding Issues: Given the discrete nature of blockchain assets and the limitations of fixed-point arithmetic in Solidity, rounding issues can inadvertently benefit one party at the expense of another. Identifying and mitigating rounding errors, especially in financial calculations, is crucial for maintaining fairness.

Unbounded Loops: Loops that don't have a fixed limit on the number of iterations can lead to out-of-gas errors, making a contract functionally unresponsive. Recognizing patterns that may lead to unbounded loops is essential for ensuring contract reliability and efficiency.

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