MX Inspector

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

Warning: Authorised use only. --probe opens an SMTP session to the target MX hosts. Use it only on systems you are allowed to test.

Install

pip install lupaxa-mx-inspector
mx-inspector --help

CLI

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
mx-inspector example.com --probe --port 587
mx-inspector example.com --probe --timeout 10
python -m lupaxa.mx_inspector --version

The tool queries MX hosts, SPF, and _dmarc.<domain>, then prints a table of decoded tags and a spoofing-posture score. On a colour terminal, names are cyan, values are green, missing is grey, and the score is coloured by grade. --no-color or NO_COLOR disables that. --probe greets each MX (banner + EHLO only) to fingerprint mail software. --port sets the SMTP probe port (default 25; use 587 for submission). --timeout sets the SMTP probe timeout (default 5 seconds). --format json writes {domain, policy, mx, spf, score, error, mx_error, spf_error} objects, plus probe when --probe is set.

Library

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)

Development

make init
make python-install-dev
make python-check

Documentation

The published guide is at https://mx-inspector.thelupaxaproject.org/.

Site Markdown lives in mkdocs/.

python -m pip install -r requirements.txt
make mkdocs-serve