# 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 1개의 Shoulder 탐지 규칙을 기반으로 한 OS Command Injection 예방 전략. ### 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 - 승인되지 않은 명령 실행 - 애플리케이션 데이터 읽기 - 보호 메커니즘 우회 ## Mitigations - 외부 프로세스 대신 라이브러리 호출을 사용하세요 - Runtime.exec()를 사용한다면 인수 배열을 받는 버전을 사용하세요 - 데이터와 코드의 분리를 자동으로 강제하는 구조화된 메커니즘을 사용하세요 ## 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