# Execution with Unnecessary Privileges (CWE-250)

The product performs an operation at a privilege level that is higher than the minimum level required, which creates new weaknesses or amplifies the consequences of other weaknesses.

**Stack:** Docker

- Prevalence: 높음 자주 악용됨
- Impact: 치명적 3개의 치명적 심각도 규칙
- Prevention: 문서화됨 10개의 수정 예시

**OWASP:** Broken Access Control (A01:2021-Broken Access Control) - #1

## Description

New weaknesses can be exposed because running with extra privileges gives the product access to resources that are not necessary. In addition, if an attacker can trigger the operation with the higher privileges, the attacker might gain root or administrator privileges.

## Prevention

### Docker

Add a USER instruction before CMD/ENTRYPOINT to run as non-root

Use a non-root user and restrictive file permissions instead of USER root or chmod 777

## Warning Signs

- [HIGH] No USER instruction before CMD/ENTRYPOINT - container runs as root
- [HIGH] CMD or ENTRYPOINT without a preceding USER instruction
- [HIGH] Dockerfile contains ...: ...
- [HIGH] explicit root user and overly permissive chmod 777 permissions

## Consequences

- 권한 획득
- 승인되지 않은 코드 실행
- 애플리케이션 데이터 읽기
- 애플리케이션 데이터 수정

## Mitigations

- 필요한 작업을 수행하는 데 필요한 최소 권한으로 코드를 실행하세요
- 구성 요소에 필요한 최소 접근 권한을 파악하고 그 권한만 부여하세요
- Just-In-Time(JIT) 권한 모델 사용을 검토하세요

## Detection

- Total rules: 10
- Critical: 3
- Languages: dockerfile, yaml

## Rules by Language

### Dockerfile (2 rules)

- **Container runs as root** [HIGH]: Detects CMD or ENTRYPOINT without a preceding USER instruction.
The container will run as root, which is a security risk.
  - Remediation: Add a USER instruction before CMD/ENTRYPOINT to run as a non-root user.

```dockerfile
USER appuser
CMD ["node", "server.js"]
```

Learn more: https://shoulder.dev/learn/docker/cwe-250/missing-user
- **Docker User and File Permissions** [HIGH]: Detects explicit root user and overly permissive chmod 777 permissions.
  - Remediation: Use a non-root user and restrictive file permissions.

```dockerfile
RUN adduser -D appuser
USER appuser
```

Learn more: https://shoulder.dev/learn/docker/cwe-250/user-permissions