# Integer Overflow or Wraparound (CWE-190)

The product performs a calculation that can produce an integer overflow or wraparound, when the logic assumes that the resulting value will always be larger than the original value.

**Stack:** Go

- Prevalence: Medium 3 languages covered
- Impact: Medium Review recommended
- Prevention: Documented 3 fix examples

**OWASP:** Security Misconfiguration (A05:2021-Security Misconfiguration) - #5

## Description

An integer overflow occurs when an arithmetic operation attempts to create a numeric value that is outside of the range that can be represented with a given number of bits. This can lead to buffer overflows, incorrect financial calculations, or security bypasses.

## Prevention

Prevention strategies for Integer Overflow based on 1 Shoulder detection rules.

### Go

Validate bounds before arithmetic operations with user-controlled integers

## Consequences

- DoS
- Execute Unauthorized Code
- Modify Application Data

## Mitigations

- Use languages or libraries that check for integer overflow
- Validate that inputs are within expected ranges
- Use safe arithmetic functions that check for overflow

## Detection

- Total rules: 3
- Languages: go, javascript, typescript, python

## Rules by Language

### Go (1 rules)

- **Integer Overflow via Unchecked Arithmetic** [MEDIUM]: User-controlled integer used in arithmetic or allocation without bounds checking.
  - Remediation: Validate bounds before arithmetic operations with user input.

```go
count, err := strconv.Atoi(r.URL.Query().Get("count"))
if err != nil || count < 0 || count > 10000 {
    return errors.New("invalid count")
}
buffer := make([]byte, count*1024)
```

Learn more: https://shoulder.dev/learn/go/cwe-190/integer-overflow