# Command Injection (CWE-78)

User input is passed unsanitized to system shell commands, allowing attackers to execute arbitrary commands on the server.

**Stack:** Python

- Prevalence: Common Found in many applications
- Impact: Critical Full server compromise
- Prevention: Avoid shell Use execFile, not exec

**OWASP:** Injection (A03:2021-Injection) - #3

## Description

This could allow attackers to execute unexpected, dangerous commands directly on the operating system. This weakness can lead to a vulnerability in environments in which the attacker does not have direct access to the operating system.

## Prevention

基于 1 条 Shoulder 检测规则的 OS Command Injection 预防策略。

### Python

Use subprocess.run with list arguments and shell=False

## Warning Signs

- [CRITICAL] untrusted user input flowing into operating system command execution
functions without proper saniti

## Consequences

- 执行未授权命令
- 读取应用程序数据
- 绕过保护机制

## Mitigations

- 使用库调用而不是外部进程
- 如果使用 Runtime.exec(),请使用接受参数数组的版本
- 使用能自动强制实现数据与代码分离的结构化机制

## Detection

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

## Rules by Language

### Python (1 rules)

- **OS Command Injection** [CRITICAL]: Detects untrusted user input flowing into operating system command execution
functions without proper sanitization.
  - Remediation: Use subprocess with argument lists and shell=False.

```python
subprocess.run(["ping", "-c", "2", ip_address], check=True)
```

Learn more: https://shoulder.dev/learn/python/cwe-78/command-injection