Invalid Port Number

HIGH

EXPOSE instruction has invalid port number. Valid ports are 1-65535.

Rule Information

Language
Docker
Category
Correctness
Author
Code Pathfinder
Last Updated
2026-01-17
Tags
dockerdockerfileportexposevalidationinput-validationcorrectnessnetworkingconfiguration
CWE References
CWE-20

Interactive Playground

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

pathfinder ci --ruleset docker/DOCKER-COR-002 --project .
Vulnerable Code
1
2
Security Rule

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Frequently Asked Questions

Common questions about Invalid Port Number

EXPOSE instruction has invalid port number. Valid ports are 1-65535.
This vulnerability is rated as HIGH severity, which means it should be addressed promptly as it poses significant security risks that could lead to unauthorized access, data leaks, or system compromise.

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 ci --ruleset docker/DOCKER-COR-002 --project .

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

  • CWE (Common Weakness Enumeration): CWE-20
  • Tags: docker, dockerfile, port, expose, validation, input-validation, correctness, networking, configuration
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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