Mail domain report: antagonist.nl

SPF

pass

SPF record published

Found

Record: v=spf1 ip4:139.144.178.31 ip4:141.138.168.81 ip4:141.138.169.50 ip4:141.138.172.133 ip4:195.211.72.55 ip4:195.211.73.208 ip4:195.211.73.223 ip4:195.211.73.55 ip6:2a01:7e01:e001:9c7::1 ip6:2a03:3c00:1337:3000::443 ip6:2a03:3c00:a001:7009::1 ip6:2a03:3c00:a001:7014::1 ip6:2a03:3c00:c001:0:f816:3eff:feb4:6e4c include:_spf.createsend.com include:spf.protection.outlook.com include:spf.patchman.co include:mail.registrar.eu include:mail.zendesk.com include:_spf.g1i.one ~all
DNS lookups: 7 of 10
Void lookups: 0 of 2

Checks

✓ No deprecated ptr mechanism #1

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

SPF record needs 7 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.antagonist.nl)

Found

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

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

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:dmarc-reports@antagonist.nl, mailto:antagonist.nl-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: default, selector1, selector2, google

Found

Selectors: default, selector1, selector2, google
_domainkey: NOERROR

Selector	Key	Flags
default	RSA 1024 bits
selector1	RSA 2048 bits
selector2	RSA 2048 bits
google	RSA 2048 bits

Checks

✓ Keys found: default, selector1, selector2, google #7

DKIM keys found for this domain with selectors: default, selector1, selector2, google
!

1024-bit DKIM key

1024-bit RSA keys are the minimum and are considered weak today: default (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 (1)
DS at parent: Yes
Algorithms: ECDSAP256SHA256 (13)
Key tags: 47684
Signatures valid until: 29 October 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 2026-10-29 #21

DNSKEY signatures are valid until 2026-10-29T00:00:00Z.

MX

warn

1 mail server

Found

Priority	Host	Records	Reverse DNS
10	antagonist-nl.o-v1.mx.microsoft	A 52.101.170.0 A 52.101.168.0 A 52.101.170.2 A 52.101.170.1 AAAA 2a01:111:f403:ca2d:: AAAA 2a01:111:f403:ca27:: AAAA 2a01:111:f403:ca2d::1 AAAA 2a01:111:f403:ca2d::2	mail-fr5p281cu00500.inbound.protection.outlook.com ✓ mail-beup281cu00100.inbound.protection.outlook.com ✓ mail-fr6p281cu00202.inbound.protection.outlook.com ✓ mail-fr4p281cu03101.inbound.protection.outlook.com ✓ mail-fr5p281cu00500.inbound.protection.outlook.com ✓ mail-beup281cu00100.inbound.protection.outlook.com ✓ mail-fr4p281cu03101.inbound.protection.outlook.com ✓ mail-fr6p281cu00202.inbound.protection.outlook.com ✓

Checks

✓ 1 MX record #9

Found 1 MX records for this domain.
✓ All hosts resolve #10

All MX records resolve to valid IP addresses.
✓ All hosts have IPv6 #11

All MX records resolve to IPv6 addresses.
!

Single MX host, no backup

Only one MX record found. For better email reliability, consider adding at least one backup MX server.

#12
✓ At most 5 MX records #13

Found 1 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 8 MX addresss have a PTR record that resolves back to them.

TLS

warn

no MTA-STS · no TLS-RPT · DANE on 1 of 1 MX hosts

Found

DANE (TLSA records)

MX host	TLSA	DNSSEC
antagonist-nl.o-v1.mx.microsoft	3 1 1 803f7447cc75b208… 3 1 1 cfd68bde4129c00a… 2 0 1 ea7a25255d111fc3… 2 0 1 c1ad7778796d20bc… 3 1 1 54883cc5f1849331…	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 1 MX host publish DNSSEC-validated TLSA records.

BIMI

info

No BIMI record

Checks

i

Not configured

BIMI shows your logo next to your mail in supporting mail clients. It requires DMARC enforcement.

#38