Mail domain report: asser.nl

SPF

pass

SPF record published

Found

Record: v=spf1 include:_spf.mlsend.com ip4:194.171.107.219 ip4:194.171.107.220 ip4:194.171.107.221 ip4:194.171.107.200 ip4:194.171.107.208 ip4:194.171.107.203 ip4:194.171.107.201 ip6:2001:610:440:2:194:171:107:219 ip6:2001:610:440:2:194:171:107:220 ip6:2001:610:440:2:194:171:107:221 ip6:2001:610:440:2:194:171:107:200 ip6:2001:610:440:2:194:171:107:208 mx include:spf.em.secureserver.net include:spf.protection.outlook.com -all
DNS lookups: 4 of 10
Void lookups: 0 of 2

Checks

✓ No deprecated ptr mechanism #1

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

SPF record needs 4 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.asser.nl)

Found

Record: v=DMARC1; p=reject; pct=100; rua=mailto:ict@asser.nl; ri=86400; aspf=r; adkim=r; fo=1
Found at: _dmarc.asser.nl

Tag	Value	Meaning
v	DMARC1	Version
p	reject	Policy
pct	100	Percentage of mail the policy applies to
rua	mailto:ict@asser.nl	Aggregate report addresses
adkim	r	DKIM alignment (r = relaxed, s = strict)
aspf	r	SPF alignment (r = relaxed, s = strict)
fo	1	Failure reporting options
ri	86400	Report interval (seconds)

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:ict@asser.nl
✓ Subdomain policy: reject #20

Subdomains are covered by policy 'reject'.
✓ Report addresses in own domain #29

All report addresses are in your own organizational domain.

DKIM

pass

Selectors: selector1

Found

Selectors: selector1
_domainkey: NOERROR

Selector	Key	Flags
selector1	RSA 2048 bits

Checks

✓ Keys found: selector1 #7

DKIM keys found for this domain with selectors: selector1
✓ Strong keys #23

DKIM keys are strong enough: selector1: RSA 2048 bits.
✓ 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: RSASHA256 (8)
Key tags: 15001, 5647
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
0	asser-nl.r-v1.mx.microsoft	A 52.101.185.24 A 52.101.91.21 A 52.101.68.21 A 52.101.209.28 AAAA 2a01:111:f403:ca3c::6 AAAA 2a01:111:f403:c967::8 AAAA 2a01:111:f403:ca48::12 AAAA 2a01:111:f403:c967::c	mail-zrxpr07cu00100.inbound.protection.outlook.com ✓ mail-matpr05cu00105.inbound.protection.outlook.com ✓ mail-db4pr02cu00205.inbound.protection.outlook.com ✓ mail-cpjpr05cu00104.inbound.protection.outlook.com ✓ mail-zrxpr04cu00106.inbound.protection.outlook.com ✓ mail-cpjpr04cu00100.inbound.protection.outlook.com ✓ mail-miypr05cu00202.inbound.protection.outlook.com ✓ mail-cpjpr05cu00204.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
asser-nl.r-v1.mx.microsoft	3 1 1 54883cc5f1849331… 2 0 1 c1ad7778796d20bc… 3 1 1 803f7447cc75b208… 3 1 1 cfd68bde4129c00a… 2 0 1 ea7a25255d111fc3…	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