Prefer COPY Over ADD

low

ADD has implicit behavior (tar extraction, URL download) that can be surprising. Use COPY unless you need ADD features

Rule Information

Language
Docker
Category
Best Practices
Author
Code Pathfinder Team
Last Updated
2024-12-10
Tags
dockerbest-practiceclarity

Interactive Playground

Experiment with the vulnerable code and security rule below. Edit the code to see how the rule detects different vulnerability patterns.

pathfinder scan --rule cpf/docker-prefer-copy
Vulnerable Code
Security Rule

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Frequently Asked Questions

Common questions about Prefer COPY Over ADD

ADD has implicit behavior (tar extraction, URL download) that can be surprising. Use COPY unless you need ADD features
This vulnerability is rated as low severity, which means it should be addressed when convenient as it represents a lower security risk but still indicates areas for improvement in code quality and security posture.

Use Code Pathfinder to scan your Docker codebase and automatically detect instances of this vulnerability pattern. Install Code Pathfinder and run the following command in your project directory:

pathfinder scan --rule cpf/docker-prefer-copy

This rule is aligned with industry-standard security frameworks and classifications:

  • Tags: docker, best-practice, clarity
Yes! Code Pathfinder allows you to customize rules to match your specific security requirements and coding standards. You can modify the detection patterns, adjust severity levels, add custom sanitizers, and configure the rule to fit your organization's security policies. The interactive playground above lets you experiment with the rule and see how it behaves with different code patterns.
When this vulnerability is detected in your code, review the flagged instances carefully. Check the "Vulnerable Code" section above for examples of insecure patterns and the "Security Rule" section to understand what the rule is looking for. Follow security best practices for Docker and consult the CWE/CVE references for detailed remediation guidance. Always test your fixes thoroughly before deploying to production.
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