Mail domain report: one.com

SPF

pass

SPF record published

Found

Record: v=spf1 include:_spf.one.com include:spf.mail.intercom.io include:mail.zendesk.com include:spf.mandrillapp.com include:servers.mcsv.net include:spf.protection.outlook.de include:secure-mailgate.com ~all
DNS lookups: 9 of 10
Void lookups: 0 of 2

Checks

✓ No deprecated ptr mechanism #1

No ptr mechanism found in SPF record.
✓ 9 of 10 DNS lookups #2

SPF record needs 9 DNS lookups (limit is 10).
✓ Ends with ~all #3

SPF record properly uses ~all to restrict unauthorized senders.
✓ Record published #6

SPF record exists for this domain.
✓ Single record #16

Exactly one SPF record is published.
✓ Valid syntax #25

All SPF mechanisms and modifiers are valid.
✓ No void lookups #26

All include/redirect targets exist.
✓ No overly broad IP ranges #27

All ip4/ip6 ranges are narrow enough.

DMARC

pass

p=reject (_dmarc.one.com)

Found

Record: v=DMARC1; p=reject; psd=n; rua=mailto:one.com-ag@dmarc-reports.g1i.one; ruf=mailto:one.com-fr@dmarc-reports.g1i.one;
Found at: _dmarc.one.com
External report address: mailto:one.com-ag@dmarc-reports.g1i.one (authorized)
External report address: mailto:one.com-fr@dmarc-reports.g1i.one (authorized)

Tag	Value	Meaning
v	DMARC1	Version
p	reject	Policy
rua	mailto:one.com-ag@dmarc-reports.g1i.one	Aggregate report addresses
ruf	mailto:one.com-fr@dmarc-reports.g1i.one	Failure report addresses
psd	n

Checks

✓ Policy: reject #4

DMARC policy is set to 'reject', which provides the strongest protection against email spoofing.
✓ Record published #5

DMARC record exists for this domain.
✓ Valid syntax #17

DMARC record syntax is valid.
✓ Applies to 100% of mail #18

DMARC policy applies to all failing mail.
✓ Aggregate reports enabled #19

Aggregate reports are sent to: mailto:one.com-ag@dmarc-reports.g1i.one
✓ Subdomain policy: reject #20

Subdomains are covered by policy 'reject'.
✓ External report addresses authorized #29

Report addresses in other domains have published their authorization.

DKIM

warn

Selectors: k1

Found

Selectors: k1
_domainkey: NOERROR

Selector	Key	Flags
k1	RSA 1024 bits

Checks

✓ Keys found: k1 #7

DKIM keys found for this domain with selectors: k1
!

1024-bit DKIM key

1024-bit RSA keys are the minimum and are considered weak today: k1 (1024 bits). Rotate to a 2048-bit key.

#23
✓ No problematic flags #24

No keys in test mode, revoked, or limited to SHA-1.

DNSSEC

pass

Signed, DS published at parent

Found

DNSKEY records: Yes (2)
DS at parent: Yes
Algorithms: ECDSAP256SHA256 (13)
Key tags: 17015, 44996
Signatures valid until: 5 November 2026, 00:00 UTC

Checks

✓ Signed, DS published at parent #8

DNSSEC is enabled for this domain (DNSKEY and DS present), providing additional security for DNS lookups.
✓ Signatures valid until 2026-11-05 #21

DNSKEY signatures are valid until 2026-11-05T00:00:00Z.

MX

warn

4 mail servers

Found

Priority	Host	Records	Reverse DNS
10	mx1.pub.mailpod12-cph3.one.com	A 104.37.34.246	mx1.pub.mailpod12-cph3.one.com ✓
10	mx2.pub.mailpod12-cph3.one.com	A 104.37.34.247	mx2.pub.mailpod12-cph3.one.com ✓
10	mx3.pub.mailpod12-cph3.one.com	A 104.37.34.248	mx3.pub.mailpod12-cph3.one.com ✓
10	mx4.pub.mailpod12-cph3.one.com	A 104.37.34.249	mx4.pub.mailpod12-cph3.one.com ✓

Checks

✓ 4 MX records #9

Found 4 MX records for this domain.
✓ All hosts resolve #10

All MX records resolve to valid IP addresses.
!

Hosts without IPv6

The following MX hosts could not be resolved to IPv6 addresses: mx1.pub.mailpod12-cph3.one.com, mx2.pub.mailpod12-cph3.one.com, mx3.pub.mailpod12-cph3.one.com, mx4.pub.mailpod12-cph3.one.com

#11
✓ Redundant MX hosts #12

Found 4 MX records, which provides redundancy for email delivery.
✓ At most 5 MX records #13

Found 4 MX records, which is within the recommended range (1-5).
✓ No localhost targets #14

No MX records pointing to localhost found.
✓ No private IP addresses #15

No MX records resolving to private IP addresses found.
✓ No CNAME targets #22

No MX records point to a CNAME.
✓ Reverse DNS confirmed #30

All 4 MX addresss have a PTR record that resolves back to them.

TLS

warn

no MTA-STS · no TLS-RPT · DANE on 4 of 4 MX hosts

Found

DANE (TLSA records)

MX host	TLSA	DNSSEC
mx1.pub.mailpod12-cph3.one.com	3 1 1 2cddc5d748a3c02a…	Yes
mx2.pub.mailpod12-cph3.one.com	3 1 1 2cddc5d748a3c02a…	Yes
mx3.pub.mailpod12-cph3.one.com	3 1 1 2cddc5d748a3c02a…	Yes
mx4.pub.mailpod12-cph3.one.com	3 1 1 2cddc5d748a3c02a…	Yes

Checks

!

Not configured

MTA-STS is not configured, so other mail servers fall back to unencrypted delivery when TLS fails or is stripped by an attacker. Publish a _mta-sts TXT record and a policy at https://mta-sts.<domain>/.well-known/mta-sts.txt.

#32
!

Not configured

MTA-STS or DANE is used without TLS-RPT, so you get no reports when senders fail to deliver because of TLS problems. Publish _smtp._tls TXT "v=TLSRPTv1; rua=mailto:...".

#35
✓ DANE on all MX hosts #36

All 4 MX hosts publish DNSSEC-validated TLSA records.

BIMI

pass

https://bimi.group-cdn.one/onecom/v2/logo.svg

Found

Record: v=BIMI1; l=https://bimi.group-cdn.one/onecom/v2/logo.svg; a=https://bimi.group-cdn.one/onecom/v2/cert.pem
Found at: default._bimi.one.com
Logo: https://bimi.group-cdn.one/onecom/v2/logo.svg
Certificate: https://bimi.group-cdn.one/onecom/v2/cert.pem

Checks

✓ Logo and certificate published #38

BIMI logo: https://bimi.group-cdn.one/onecom/v2/logo.svg; certificate: https://bimi.group-cdn.one/onecom/v2/cert.pem
✓ DMARC meets BIMI requirements #39

DMARC is enforced on all mail, as BIMI requires.