cat4school.de

01Overview 02DNS 03WHOIS 04Subdomains 05Email 06TLS

Checking SPF, DKIM, and DMARC

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digga is open source under AGPL 3.0.

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Checking SPF, DKIM, and DMARC

Email authentication

Spoofing protection has gaps that need attention.

0Pass
0Warning
2Fail
4Not set

SPF

Fail

Authorizes which servers may send mail for the domain

SPF is published but misconfigured.

Policy: ~all
DNS lookups: >10 / 10

Ends in ~all (softfail): unauthorized senders are marked, not rejected.
SPF evaluation needs >10 DNS lookups, over the limit of 10. Receivers return permerror and SPF fails.

v=spf1 include:mailgun.org include:_spf.firebasemail.com include:_spf.hostedemail.com include:hover.com ~all

DKIM

Not set

Cryptographically signs outgoing mail (best-effort selector probe)

No DKIM key found for common selectors.

Selectors probed: 32

DKIM selectors cannot be enumerated from DNS, so this only probes well-known selectors. A negative result is not proof that DKIM is missing.

DMARC

Fail

Tells receivers what to do with mail that fails SPF and DKIM

No DMARC record. Failing mail is not actively rejected or quarantined.

No v=DMARC1 TXT record found at _dmarc.cat4school.de
DMARC ties SPF and DKIM together and enables reporting.

MTA-STS

Not set

Enforces TLS for inbound mail and prevents downgrade attacks

No MTA-STS policy. Inbound mail can be delivered without TLS.

TLS-RPT

Not set

Receives reports about TLS delivery failures

No TLS-RPT record. You get no reports about failed TLS delivery.

BIMI

Not set

Displays your verified brand logo in supporting inboxes

No BIMI record. No brand logo is published for inboxes.

Checks query live DNS over Cloudflare and the public MTA-STS policy endpoint. DKIM selectors cannot be listed from DNS, so DKIM detection probes common provider selectors only.