Networking DNS Check

I own and manage a portfolio of well over twenty corporate domains and need a reliable way to catch any “dangling” DNS entries—those CNAME, A, or AAAA records that still point to cloud resources or hosts that are no longer under my control. A single forgotten record can expose the brand to takeover risks, so the goal is a Python-based solution that can sweep every zone file, identify vulnerable records, and give me clear next steps to fix them.

What the script should do
• Parse each domain’s authoritative name servers and enumerate every DNS record.
• Flag any record that resolves to unclaimed or expired resources on platforms such as AWS, Azure, GCP, GitHub Pages, Heroku, etc.
• Produce a concise report (CSV or JSON) that lists: domain, record type, offending value, risk level, and a recommended remediation action (delete, update, or claim).
• Exit with a non-zero code when at least one risky record is found so I can wire it into CI/CD later.

Technical expectations
• Written purely in Python 3.x with no external binaries required.
• Modular design (functions or classes) so I can extend provider checks over time.
• Works cross-platform (Linux/Mac/Windows) and runs from the CLI with simple flags:
python detect_dangling.py --domains domains.txt --output report.csv

Acceptance criteria
1. Running the script against a sample zone file I provide returns the exact number of intentionally exposed test records.
2. The report includes every required column and matches the format agreed upon.
3. Clear README covering setup, dependencies (dnspython, requests, etc.), and example usage.

If you have previous experience building security tooling or DNS scanners, let me see a short demo or repo link when you bid.