Mail domain report: leidseschouwburg-stadsgehoorzaal.nl

SPF

pass

SPF record published

Found

Record: v=spf1 ip4:46.44.147.192/21 include:spf.protection.outlook.com include:spf.mtasv.net include:servers.mcsv.net include:spf.slik.eu include:sendgrid.net include:amazonses.com include:_spf.mailer.twinfield.com include:spf.mailinglijst.nl -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.leidseschouwburg-stadsgehoorzaal.nl)

Found

Record: v=DMARC1; p=reject; rua=mailto:ko52x3d5ox@rua.dmarc.collabite.nl
Found at: _dmarc.leidseschouwburg-stadsgehoorzaal.nl
External report address: mailto:ko52x3d5ox@rua.dmarc.collabite.nl (authorized)

Tag	Value	Meaning
v	DMARC1	Version
p	reject	Policy
rua	mailto:ko52x3d5ox@rua.dmarc.collabite.nl	Aggregate 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:ko52x3d5ox@rua.dmarc.collabite.nl
✓ 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, selector1, selector2, s1, s2

Found

Selectors: k1, selector1, selector2, s1, s2
_domainkey: NOERROR

Selector	Key	Flags
k1	RSA 1024 bits
selector1	RSA 2048 bits
selector2	RSA 2048 bits
s1	RSA 2048 bits
s2	RSA 1024 bits

Checks

✓ Keys found: k1, selector1, selector2, s1, s2 #7

DKIM keys found for this domain with selectors: k1, selector1, selector2, s1, s2
!

1024-bit DKIM key

1024-bit RSA keys are the minimum and are considered weak today: k1 (1024 bits), s2 (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: 42530, 51734
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

1 mail server

Found

Priority	Host	Records	Reverse DNS
10	leidseschouwburgstadsgehoorzaal-nl04b.c-v1.mx.microsoft	A 52.101.73.120 A 52.101.68.21 A 52.101.103.162 A 52.101.91.21 AAAA 2a01:111:f403:ca09::20 AAAA 2a01:111:f403:c967::c AAAA 2a01:111:f403:ca48::12 AAAA 2a01:111:f403:ca48::a	mail-am7pr02cu00300.inbound.protection.outlook.com ✓ mail-db4pr02cu00205.inbound.protection.outlook.com ✓ mail-miypr03cu00202.inbound.protection.outlook.com ✓ mail-matpr05cu00105.inbound.protection.outlook.com ✓ mail-as8pr05cu00400.inbound.protection.outlook.com ✓ mail-cpjpr05cu00204.inbound.protection.outlook.com ✓ mail-miypr05cu00202.inbound.protection.outlook.com ✓ mail-miypr02cu00202.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

MTA-STS testing · TLS-RPT · DANE on 1 of 1 MX hosts

Found

MTA-STS record: v=STSv1; id=20241015153758403301;
Policy URL: https://mta-sts.leidseschouwburg-stadsgehoorzaal.nl/.well-known/mta-sts.txt
Mode: testing
Allowed MX: leidseschouwburgstadsgehoorzaal-nl04b.mail.protection.outlook.com
Max age: 86400 seconds
TLS-RPT record: v=TLSRPTv1;rua=mailto:ko52x3d5ox@tls.dmarc.collabite.nl

DANE (TLSA records)

MX host	TLSA	DNSSEC
leidseschouwburgstadsgehoorzaal-nl04b.c-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

✓ Record published #32

MTA-STS record found with id 20241015153758403301.
!

Policy in testing mode

With mode: testing, senders only report TLS problems (via TLS-RPT) and still deliver without TLS. Switch to mode: enforce once reports are clean.

#33
!

MX hosts missing from policy

These MX hosts are not listed in the MTA-STS policy (mx: leidseschouwburgstadsgehoorzaal-nl04b.mail.protection.outlook.com): leidseschouwburgstadsgehoorzaal-nl04b.c-v1.mx.microsoft. This will break delivery once the policy is enforced.

#34
✓ Reports enabled #35

TLS reports are sent to: mailto:ko52x3d5ox@tls.dmarc.collabite.nl
✓ 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