Mail domain report: zyxel.com

SPF

pass

SPF record published

Found

Record: v=spf1 ip4:24.110.64.0/18 ip4:216.221.160.0/19 ip4:206.55.144.0/20 ip4:199.255.192.0/22 ip4:199.127.232.0/22 ip4:76.223.176.0/20 ip4:76.223.128.0/19 ip4:69.169.224.0/20 ip4:54.240.0.0/17 ip4:23.251.224.0/19 ip4:23.249.208.0/20 ip4:219.87.158.112/29 ip4:59.124.182.147/32 ip4:66.85.124.0/25 ip4:208.75.120.0/22 ip4:205.207.104.0/22 ip4:216.24.224.0/20 ip4:216.27.12.144/28 ip4:216.27.14.0/26 ip4:216.27.14.64/27 ip4:216.27.8.32/28 ip4:216.27.20.128/27 ip4:216.27.22.160/27 ip4:216.27.22.192/27 ip4:185.131.228.0/24 ip4:185.131.229.0/25 ip4:65.98.250.0/24 ip4:65.98.206.0/24 ip4:65.98.214.0/24 ip4:65.98.146.0/24 ip4:65.98.228.0/24 ip4:69.63.150.0/23 include:spf.ess.barracudanetworks.com include:_spf.google.com include:mail.zendesk.com include:sendgrid.net include:2533502.spf07.hubspotemail.net include:_spf.rulemailer.com ~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

fail

p=none (_dmarc.zyxel.com)

Found

Record: v=DMARC1; p=none; rua=mailto:aggregate_reports@zyxel.com,mailto:dmarc@rule.se,mailto:dmarc_reports@zyxel.com; ruf=mailto:forensic_reports@zyxel.com,mailto:authfail@rule.se; fo=1; adkim=r; aspf=r
Found at: _dmarc.zyxel.com
External report address: mailto:dmarc@rule.se (authorized)
External report address: mailto:authfail@rule.se (authorized)

Tag	Value	Meaning
v	DMARC1	Version
p	none	Policy
rua	mailto:aggregate_reports@zyxel.com,mailto:dmarc@rule.se,mailto:dmarc_reports@zyxel.com	Aggregate report addresses
ruf	mailto:forensic_reports@zyxel.com,mailto:authfail@rule.se	Failure report addresses
adkim	r	DKIM alignment (r = relaxed, s = strict)
aspf	r	SPF alignment (r = relaxed, s = strict)
fo	1	Failure reporting options

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.
✓ Aggregate reports enabled #19

Aggregate reports are sent to: mailto:aggregate_reports@zyxel.com, mailto:dmarc@rule.se, mailto:dmarc_reports@zyxel.com
✓ External report addresses authorized #29

Report addresses in other domains have published their authorization.

DKIM

warn

Selectors: google, s1, s2

Found

Selectors: google, s1, s2
_domainkey: NOERROR

Selector	Key	Flags
google	RSA 1024 bits
s1	RSA 2048 bits
s2	RSA 1024 bits

Checks

✓ Keys found: google, s1, s2 #7

DKIM keys found for this domain with selectors: google, s1, s2
!

1024-bit DKIM key

1024-bit RSA keys are the minimum and are considered weak today: google (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

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

2 mail servers

Found

Priority	Host	Records	Reverse DNS
10	d88700a.ess.barracudanetworks.com	A 209.222.82.252 A 209.222.82.253 A 209.222.82.255	mail.ess.barracuda.com ✓ mail.ess.barracuda.com ✓ mail.ess.barracuda.com ✓
20	d88700b.ess.barracudanetworks.com	A 209.222.82.253 A 209.222.82.255 A 209.222.82.252	mail.ess.barracuda.com ✓ mail.ess.barracuda.com ✓ mail.ess.barracuda.com ✓

Checks

✓ 2 MX records #9

Found 2 MX records for this domain.
✓ All hosts resolve #10

All MX records resolve to valid IP addresses.
!

Hosts without IPv6

The following MX hosts could not be resolved to IPv6 addresses: d88700a.ess.barracudanetworks.com, d88700b.ess.barracudanetworks.com

#11
✓ 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 6 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
d88700a.ess.barracudanetworks.com	none	-
d88700b.ess.barracudanetworks.com	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