Integer Overflows/Underflows

Integer Overflows and Underflows occur when mathematical operations exceed the storage limits of a variable, causing unexpected behavior. These vulnerabilities allow attackers to manipulate values in ways that can break contract logic.

How They Work

1. Integer Overflow: When a value exceeds the maximum limit of its data type, it wraps around to the minimum value. Example:

   solidity
   
   uint8 x = 255; // Max value for uint8
   x += 1;       // Overflow: x becomes 0

2. Integer Underflow: When a value is reduced below the minimum limit of its data type, it wraps around to the maximum value. Example:

   solidity
   
   uint8 x = 0; // Min value for uint8
   x -= 1;     // Underflow: x becomes 255

Real-Life Impact

Attackers exploit overflows/underflows to:

• Mint extra tokens.

• Bypass balance checks.

• Gain unauthorized access to funds.