Trick or Treat

Summary

While strict equality (===) might seem intuitive for checking balances, it's not suitable for financial calculations due to precision issues, rounding errors, and potential security vulnerabilities. Using non-strict comparisons like >= or <= is generally safer and more flexible when dealing with Ether or token balances in smart contracts.

so Don't use strict equality to determine if an account has enough Ether or tokens.

Vulnerability Details

When dealing with Ether or tokens, we're typically working with decimal values. However, Ethereum stores all values as integers. This means that even small fractions of a unit can cause precision loss when compared using strict equality.

Due to the nature of floating-point arithmetic (even though Ethereum uses integer arithmetic), small rounding differences can occur. These differences can cause strict equality checks to fail, even when the amounts are practically equivalent.

Impact

Financial calculations often involve decimal places, which can lead to precision loss when using integer comparisons ,Small rounding differences can cause strict equality checks to fail even when the amounts are practically equivalent.

Tools Used

Slither,AI

Recommendations

Instead of using strict equality, it's generally better to use greater-than-or-equal-to (>=) or less-than-or-equal-to (<=) comparisons. These allow for some flexibility in the comparison while still maintaining the desired logic