Mail domain report: zum.de

SPF

pass

SPF record published

Found

Record: v=spf1 mx ip4:46.4.65.203/32 mx:metis.zum.de mx:zumserver.zum.de ip4:88.99.253.153/32 ip4:116.202.233.184/32 ip4:168.119.145.97/32 ip6:2a01:4f8:251:85d::2 ip4:176.9.48.202 ip6:2a01:4f8:150:64c5::2 mx:mail.zum.de -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

fail

p=none (_dmarc.zum.de)

Found

Record: v=DMARC1;p=none
Found at: _dmarc.zum.de

Tag	Value	Meaning
v	DMARC1	Version
p	none	Policy

Checks

✗

Policy: none (monitoring only)

DMARC policy is set to 'none', which only monitors but doesn't protect against spoofing. Consider upgrading to 'quarantine' or ideally 'reject'.

#4
✓ Record published #5

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

DMARC record syntax is valid.
!

No aggregate reports (rua)

DMARC record has no rua tag, so you receive no aggregate reports about who sends mail as your domain. Add rua=mailto:...

#19

DKIM

warn

Selectors: dkim, mail

Found

Selectors: dkim, mail
_domainkey: NOERROR

Selector	Key	Flags
dkim	RSA 2048 bits
mail	RSA 1024 bits	test mode (t=y)

Checks

✓ Keys found: dkim, mail #7

DKIM keys found for this domain with selectors: dkim, mail
!

1024-bit DKIM key

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

#23
!

Key in test mode

These keys have t=y, so receivers treat DKIM failures as a test: mail. Remove t=y once DKIM works.

#24

DNSSEC

warn

Not signed

Found

DNSKEY records: No (0)
DS at parent: No

Checks

!

Not enabled

DNSSEC is not enabled for this domain. Consider enabling DNSSEC to protect against DNS spoofing attacks.

#8

MX

pass

2 mail servers

Found

Priority	Host	Records	Reverse DNS
5	mail.zum.de	A 176.9.48.202 AAAA 2a01:4f8:150:64c5::2	mail.zum.de ✓ mail.zum.de ✓
10	zumserver.zum.de	A 46.4.65.203 AAAA 2a01:4f8:140:23eb::2	zumserver.zum.de ✓ metis.zum.de ✓

Checks

✓ 2 MX records #9

Found 2 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.
✓ Redundant MX hosts #12

Found 2 MX records, which provides redundancy for email delivery.
✓ At most 5 MX records #13

Found 2 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 0 of 2 MX hosts

Found

DANE (TLSA records)

MX host	TLSA	DNSSEC
mail.zum.de	none	-
zumserver.zum.de	none	-

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
i

Not configured

TLS-RPT lets senders report TLS delivery problems to you. It is most useful together with MTA-STS or DANE.

#35
i

Not used

No MX host publishes TLSA records. DANE lets senders verify your mail server's certificate through DNSSEC; it requires DNSSEC on the MX host's zone.

#36

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