comcast.com is a business email domain

comcast.com is an organization domain, and its published records stop mail being forged as it.

Corporate

93 /100

Strong

Email authentication report card

What comcast.com publishes in DNS to stop other people sending mail in its name, read record by record.

2 pass 3 weak

Can mail be forged as this domain?

No, a forgery is rejected

DMARC is set to p=reject and enforced on every message, so a receiver that honours it throws away any mail that fails alignment for this domain.

  • Weak

    SPF ~all

    The record ends in ~all. Mail from a host outside the list is only marked, not rejected, so it usually still arrives.

  • Pass

    DMARC p=reject

    Receivers are asked to reject any message that fails DMARC. This is the strongest published setting.

  • Weak

    MTA-STS Not published

    No MTA-STS policy, so a sending server has nothing that tells it to insist on verified TLS for this domain.

  • Pass

    DNSSEC Signed

    The zone is signed, so the MX, SPF and DMARC answers above cannot be quietly rewritten in transit.

  • Weak

    TLS-RPT Not published

    No reporting address, so failed TLS deliveries to this domain go unnoticed by its owner.

Why it scores 93?

  1. Registered more than five years ago.
  2. DMARC is published and enforced, so forged mail is rejected or quarantined.
  3. Accepts mail through 2 MX hosts.

What to publish to close the gaps

The records comcast.com is missing, in the order they are worth doing. Owner names are written out in full, so they work whether your DNS panel wants a full name or a relative one.

  1. Tighten SPF to -all

    Namecomcast.com
    TypeTXT
    Valuev=spf1 <your existing mechanisms> -all

    Keep the mechanisms you already have and change the final qualifier. Anything softer leaves the forgery path open.

  2. Publish an MTA-STS policy

    Name_mta-sts.comcast.com
    TypeTXT
    Valuev=STSv1; id=<a version string you bump on every change>

    Serve the policy body at https://mta-sts.comcast.com/.well-known/mta-sts.txt, start it in testing mode, then switch it to enforce so senders refuse to deliver over an unverified connection.

  3. Publish a TLS reporting address

    Name_smtp._tls.comcast.com
    TypeTXT
    Valuev=TLSRPTv1; rua=mailto:[email protected]

    Without it, a sending server that could not negotiate TLS with your mail hosts has nowhere to tell you.

Questions about comcast.com

Every answer below is generated from the stored record for this domain.

Is comcast.com a disposable email domain?
No. We classify comcast.com as corporate, not as a disposable mailbox service.
Is comcast.com spoofable?
No, a forgery is rejected. DMARC is set to p=reject and enforced on every message, so a receiver that honours it throws away any mail that fails alignment for this domain.
Does comcast.com publish SPF and DMARC?
comcast.com publishes an SPF record, though it does not end in -all, so hosts outside the list are not treated as forgeries. DMARC is published and enforced, so a failing message is rejected or quarantined.
Who handles email for comcast.com?
Mail for comcast.com is handled by Proofpoint, which carries 18 other domains we track.
How old is the comcast.com domain?
The comcast.com domain was registered 31 years ago. The registrar of record is CSC Corporate Domains, Inc.
How do I block comcast.com on my signup form?
We do not classify comcast.com as disposable, so blocking it outright would turn away real people. If you want to act on it, decide on the signals listed above rather than the name.
Can I trust email from comcast.com?
comcast.com scores 93 out of 100, which is a strong band. The score is a summary of the classification, infrastructure, authentication, reputation and lifecycle signals we hold, not a judgment about any individual sender at that domain.

Last verified . We recheck every domain on a schedule, and this report changes only when its records or its verdict do.