Mail domain report: rustdesk.com

SPF

pass

SPF record published

Found

Record: v=spf1 include:spf.protection.outlook.com include:_spf.google.com include:amazonses.com include:zohomail.com ~all
DNS lookups: 5 of 10
Void lookups: 0 of 2

Checks

✓ No deprecated ptr mechanism #1

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

SPF record needs 5 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.rustdesk.com)

Found

Record: v=DMARC1; p=quarantine; rua=mailto:3aff63aeaa4640ea88c09f3990aeb730@dmarc-reports.cloudflare.net,mailto:dmarcreport@rustdesk.com; ruf=mailto:dmarcreport@rustdesk.com; pct=5; adkim=r; aspf=r
Found at: _dmarc.rustdesk.com
External report address: mailto:3aff63aeaa4640ea88c09f3990aeb730@dmarc-reports.cloudflare.net (authorized)

Tag	Value	Meaning
v	DMARC1	Version
p	quarantine	Policy
pct	5	Percentage of mail the policy applies to
rua	mailto:3aff63aeaa4640ea88c09f3990aeb730@dmarc-reports.cloudflare.net,mailto:dmarcreport@rustdesk.com	Aggregate report addresses
ruf	mailto:dmarcreport@rustdesk.com	Failure report addresses
adkim	r	DKIM alignment (r = relaxed, s = strict)
aspf	r	SPF 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 5% of mail

DMARC policy only applies to 5% of failing mail (pct=5). Raise pct to 100 once you are confident in your setup.

#18
✓ Aggregate reports enabled #19

Aggregate reports are sent to: mailto:3aff63aeaa4640ea88c09f3990aeb730@dmarc-reports.cloudflare.net, mailto:dmarcreport@rustdesk.com
✓ Subdomain policy: quarantine #20

Subdomains are covered by policy 'quarantine'.
✓ External report addresses authorized #29

Report addresses in other domains have published their authorization.

DKIM

warn

Selectors: mail, selector1, google

Found

Selectors: mail, selector1, google
_domainkey: NOERROR

Selector	Key	Flags
mail	public key is not valid base64
selector1	RSA 2048 bits
google	RSA 2048 bits

Checks

✓ Keys found: mail, selector1, google #7

DKIM keys found for this domain with selectors: mail, selector1, google
!

Unreadable DKIM key

These keys could not be parsed, so signatures made with them will fail: mail (public key is not valid base64).

#23
✓ No problematic flags #24

No keys in test mode, revoked, or limited to SHA-1.

DNSSEC

warn

Signed, but no DS at parent

Found

DNSKEY records: Yes (2)
DS at parent: No
Algorithms: ECDSAP256SHA256 (13)
Key tags: 34505, 2371
Signatures valid until: 29 November 2026, 16:49 UTC

Checks

!

Signed, but no DS at parent

The zone is signed (DNSKEY present) but the parent has no DS record, so the chain of trust is incomplete. Publish the DS record at your registrar.

#8
✓ Signatures valid until 2026-11-29 #21

DNSKEY signatures are valid until 2026-11-29T16:49:52Z.

MX

pass

5 mail servers

Found

Priority	Host	Records	Reverse DNS
1	aspmx.l.google.com	A 142.251.127.26 AAAA 2a00:1450:4001:c21::1b	lcfrai-in-f26.1e100.net ✓ lcfrai-in-f27.1e100.net ✓
5	alt1.aspmx.l.google.com	A 142.250.147.27 AAAA 2a00:1450:4025:c01::1b	rd-in-f27.1e100.net ✓ rd-in-f27.1e100.net ✓
5	alt2.aspmx.l.google.com	A 172.253.152.27 AAAA 2a00:1450:4010:c22::1a	yulpptr-in-f27.1e100.net ✓ yulpptr-in-f26.1e100.net ✓
10	alt3.aspmx.l.google.com	A 192.179.20.26 AAAA 2404:6800:4000:1027::1a	ncboms-in-f26.1e100.net ✓ ncboms-in-f26.1e100.net ✓
10	alt4.aspmx.l.google.com	A 192.178.158.27 AAAA 2404:6800:4013:813::1b	lcdels-in-f27.1e100.net ✓ lcdels-in-f27.1e100.net ✓

Checks

✓ 5 MX records #9

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

Found 5 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 10 MX addresss have a PTR record that resolves back to them.

TLS

warn

MTA-STS testing · TLS-RPT · DANE on 0 of 5 MX hosts

Found

MTA-STS record: v=STSv1; id=20260929;
Policy URL: https://mta-sts.rustdesk.com/.well-known/mta-sts.txt
Mode: testing
Allowed MX: aspmx.l.google.com, *.aspmx.l.google.com
Max age: 86400 seconds
TLS-RPT record: v=TLSRPTv1; rua=mailto:no-reply@rustdesk.com

DANE (TLSA records)

MX host	TLSA	DNSSEC
aspmx.l.google.com	none	-
alt1.aspmx.l.google.com	none	-
alt2.aspmx.l.google.com	none	-
alt3.aspmx.l.google.com	none	-
alt4.aspmx.l.google.com	none	-

Checks

✓ Record published #32

MTA-STS record found with id 20260929.
!

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
✓ All MX hosts covered #34

Every MX host matches an mx: line of the MTA-STS policy.
✓ Reports enabled #35

TLS reports are sent to: mailto:no-reply@rustdesk.com
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