usd.de

Checked 22 October 2026, 00:50 UTC · via 8.8.8.8
!Passed with warnings
23 passed 6 warnings 0 failed 3 info

SPF

pass

SPF record published

Found

Record
v=spf1 ip4:212.19.54.35 ip4:82.98.105.129 ip6:2a02:2e0:41e:2500::35 include:spf.protection.outlook.com -all
DNS lookups
1 of 10
Void lookups
0 of 2

Checks

  • ✓ No deprecated ptr mechanism #1
    No ptr mechanism found in SPF record.
  • ✓ 1 of 10 DNS lookups #2
    SPF record needs 1 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

warn

p=quarantine (_dmarc.usd.de)

Found

Record
v=DMARC1; p=quarantine; rua=mailto:dmarc-rua@usd.de; adkim=r; aspf=r
Found at
_dmarc.usd.de
TagValueMeaning
vDMARC1Version
pquarantinePolicy
ruamailto:dmarc-rua@usd.deAggregate report addresses
adkimrDKIM alignment (r = relaxed, s = strict)
aspfrSPF alignment (r = relaxed, s = strict)

Checks

  • !
    Policy: quarantine
    DMARC policy is set to 'quarantine'. Consider upgrading to 'reject' for stronger protection once you've verified legitimate emails are passing authentication.
    #4
  • ✓ 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-rua@usd.de
  • ✓ Subdomain policy: quarantine #20
    Subdomains are covered by policy 'quarantine'.
  • ✓ Report addresses in own domain #29
    All report addresses are in your own organizational domain.

DKIM

warn

Selectors: selector1, selector2

Found

Selectors
selector1, selector2
_domainkey
NOERROR
SelectorKeyFlags
selector1RSA 1024 bits
selector2RSA 1024 bits

Checks

  • ✓ Keys found: selector1, selector2 #7
    DKIM keys found for this domain with selectors: selector1, selector2
  • !
    1024-bit DKIM key
    1024-bit RSA keys are the minimum and are considered weak today: selector1 (1024 bits), selector2 (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

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

warn

3 mail servers

Found

PriorityHostRecordsReverse DNS
0usd-de.mail.protection.outlook.comA 52.101.168.0 A 52.101.170.0 A 52.101.170.1 A 52.101.170.2 AAAA 2a01:111:f403:ca2d::2 AAAA 2a01:111:f403:ca27:: AAAA 2a01:111:f403:ca2d::1 AAAA 2a01:111:f403:ca2d::mail-beup281cu00100.inbound.protection.outlook.com ✓ mail-fr5p281cu00500.inbound.protection.outlook.com ✓ mail-fr4p281cu03101.inbound.protection.outlook.com ✓ mail-fr6p281cu00202.inbound.protection.outlook.com ✓ mail-fr6p281cu00202.inbound.protection.outlook.com ✓ mail-beup281cu00100.inbound.protection.outlook.com ✓ mail-fr4p281cu03101.inbound.protection.outlook.com ✓ mail-fr5p281cu00500.inbound.protection.outlook.com ✓
20mail4.usd.deA 82.98.105.129mail4.usd.de ✓
32767ms36138564.msv1.invalid(does not resolve)

Checks

  • ✓ 3 MX records #9
    Found 3 MX records for this domain.
  • !
    Hosts without IP addresses
    The following MX hosts could not be resolved to IP addresses: ms36138564.msv1.invalid
    #10
  • !
    Hosts without IPv6
    The following MX hosts could not be resolved to IPv6 addresses: mail4.usd.de, ms36138564.msv1.invalid
    #11
  • ✓ Redundant MX hosts #12
    Found 3 MX records, which provides redundancy for email delivery.
  • ✓ At most 5 MX records #13
    Found 3 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 9 MX addresss have a PTR record that resolves back to them.

TLS

warn

no MTA-STS · no TLS-RPT · DANE on 0 of 3 MX hosts

Found

DANE (TLSA records)

MX hostTLSADNSSEC
usd-de.mail.protection.outlook.comnone-
mail4.usd.denone-
ms36138564.msv1.invalidnone-

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