# Unchecked Return Value (CWE-252)

The product does not check the return value from a method or function, which can prevent it from detecting unexpected states and conditions.

**Stack:** Go

- Prevalence: 中 覆盖 2 种语言
- Impact: 高 1 条严重级别为高的规则
- Prevention: 已记录 2 个修复示例

**OWASP:** Insecure Design (A04:2021-Insecure Design) - #4

## Description

When return values are not checked, the program may continue execution in an error state or with incorrect data, potentially leading to security vulnerabilities.

## Prevention

基于 1 条 Shoulder 检测规则的 Unchecked Return Value 预防策略。

### Go

Replace blank identifier _ with err and check error return values

## Consequences

- 拒绝服务 (DoS)
- 执行未授权代码
- 修改应用程序数据

## Mitigations

- 始终检查函数的返回值
- 使用编译器警告检测未检查的返回值
- 适当地处理错误情况

## Detection

- Total rules: 2
- Languages: go, javascript, typescript

## Rules by Language

### Go (1 rules)

- **Unchecked Error Return Values** [MEDIUM]: Error return value ignored using blank identifier (_).
  - Remediation: Check all error return values and handle appropriately.

```go
data, err := ioutil.ReadFile(path)
if err != nil {
    return fmt.Errorf("failed to read file: %w", err)
}
```

Learn more: https://shoulder.dev/learn/go/cwe-252/unchecked-errors