[ Free tool · DNS & Mail Servers ]
CNAME Lookup
Follow a CNAME chain and catch a dangling target before someone else does.
[ About this tool ]
This CNAME lookup follows the full alias chain and flags dangling targets that an attacker could claim for subdomain takeover.
How to read the results
- ›A chain ending in NXDOMAIN is dangling.
- ›Remove CNAMEs for services you no longer use.
Frequently asked questions
What is subdomain takeover?
When a CNAME points to a deleted cloud resource, anyone can re-create it and serve content or send mail from your subdomain.
Learn more in our guide: Email Security: Stop Spoofing, Phishing and BEC
Enterprise provenance
Why top financial institutions and governments retired their email security dashboards.
Traditional email authentication platforms sell you a dashboard and ask your engineers to do the labour. In high-stakes environments, manual oversight means delayed enforcement, configuration drift and unmonitored shadow domains.
EmailAuth is the agentic email provenance platform. Our agents enforce p=reject, keep third-party senders aligned and move your domains to full RFC 9989 compliance, the new DMARC standard,, with human-in-the-loop auditability.
SaaS · Dedicated tenancy · Air-gapped on-prem · BYOK encryption
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