The Lupaxa Security Toolbox
Part of The Lupaxa Project

lupaxa-mx-inspector

Look up a domain's MX hosts, SPF, and DMARC policy from public DNS, with an optional SMTP banner probe.

Features

• Query MX records (priority and host)
• Query apex TXT for SPF (v=spf1)
• Query _dmarc.<domain> for the published TXT record
• Decode common DMARC tags (p, sp, rua, ruf, alignment, and more)
• Score DNS-only spoofing posture (open / monitoring / enforcing / locked down)
• Optional --probe SMTP banner / EHLO fingerprint (no authentication, no mail)
• Human-readable table (colour on a TTY; --no-color or NO_COLOR to disable), or JSON
• Library API (lookup_dmarc / lookup_mx / lookup_spf / score_posture / probe_smtp) and CLI (mx-inspector)
• Fully typed, linted, formatted, and tested

Installation

From PyPI

pip install lupaxa-mx-inspector

From source (development mode)

pip install -e ".[dev]"

Requires Python 3.10+. Runtime dependencies: dnspython, prettytable, colored.

Library quick start

from lupaxa.mx_inspector import lookup_dmarc, lookup_mx, lookup_spf, score_posture

policy = lookup_dmarc("example.com")
hosts = lookup_mx("example.com")
spf = lookup_spf("example.com")
score = score_posture(policy, mx_hosts=hosts, spf_records=spf)
print(policy["p"], score.value, score.grade)

CLI quick start

mx-inspector --help
mx-inspector example.com
mx-inspector example.com example.org
mx-inspector example.com --format json
mx-inspector example.com --no-color
mx-inspector example.com --probe --port 587

You can also run the CLI as a module:

python -m lupaxa.mx_inspector --help
python -m lupaxa.mx_inspector --version

Documentation

Online documentation:

Documentation

Source repository:

GitHub

Serve docs locally

From a clone of the repository:

make mkdocs-serve

Then open the local URL printed by MkDocs in your browser.

Development

Clone the repository and install with Make:

make init                # first-time makefile-skills checkout
make python-install-dev  # editable install with [dev]
make python-check        # lint, type-check, and test