notion.so
The three core checks pass. What is missing is the transport and trust layer around them.
4 of 8 checks pass · 0 tools visible in DNS · nothing urgent
1 · Authentication and transport
SPF
PassValid, soft failAnything not on the list is accepted but marked. Google recommends ~all; with DMARC enforced it is as strong as -all.
v=spf1 ~all
DKIM
Pass1 key foundSelectors cf2024-1 publish a public key.
cf2024-1._domainkey
DMARC
PassPartial (p=quarantine)Failing mail goes to spam. One step from full enforcement.
v=DMARC1; p=quarantine; pct=100; rua=mailto:re+1b3a27dd30bc@inbound.dmarcdigests.com;
MX
ReviewNo MX recordsThe domain cannot receive mail. Fine for a send-only domain, a problem for a company domain.
MTA-STS
ReviewNot publishedSending servers cannot tell that this domain requires TLS, so inbound mail can be downgraded to plain text by anyone on the path.
TLS-RPT
OptionalNot publishedNobody is told when TLS to this domain fails. Cheap to add once MTA-STS is in place.
BIMI
PassPublishedLogo record found and DMARC qualifies. Yahoo shows it from the record; Gmail and Apple Mail also need a VMC or CMC certificate (the a= tag).
v=BIMI1; l=https://vmc.digicert.com/ae66f82a-dd47-4f08-9fd9-fd865f1d0b30.svg; a=https://vmc.digicert.com/ae66f82a-dd47-4f08-9fd9-fd865f1d0b30.pem
DNSSEC
OptionalNot signedOptional. Signing the zone protects every record in this report from tampering.
2 · Tools visible in DNS
No known tool matched. The domain may run a custom setup, or tools we don't fingerprint yet. Absence here is not evidence of absence.
Only tools that leave a DNS trace appear. A shared DKIM selector is attributed only when its CNAME target names the vendor.
3 · Sender requirements (Google, Yahoo, Microsoft)
| Requirement | Applies to | Status | Note |
|---|---|---|---|
| Authenticate with SPF or DKIM | GoogleYahooMicrosoft | Verified | At least one method is in place. |
| Bulk senders: both SPF and DKIM | GoogleYahoo | Verified | Both are present. |
| Publish a DMARC record (p=none is enough) | GoogleYahooMicrosoft | Verified | Policy is p=quarantine. |
| From: domain aligns with SPF or DKIM | GoogleYahooMicrosoft | Not checkable here | Needs a real message. The Send-a-Test report will check this. |
| Valid forward and reverse DNS for sending IPs | GoogleYahoo | Not checkable here | Depends on the sending server, not the domain. |
| Encrypt in transit (TLS) | GoogleYahoo | Not checkable here | Outbound TLS depends on your sending tool; MTA-STS would cover inbound. |
| One-click unsubscribe (RFC 8058) for marketing mail | GoogleYahoo | Not checkable here | A message header, not a DNS record. Microsoft recommends it rather than requiring it. |
| Spam complaint rate under 0.1% (0.3% is the hard limit) | GoogleYahoo | Not checkable here | Read it in Google Postmaster Tools and Yahoo Sender Hub. Google’s target is 0.1%; 0.3% is where enforcement starts. |
4 · What to fix, in order
-
P2
Finish DMARC at p=reject
Quarantine still delivers spoofed mail, just into spam.
Publish at_dmarc.notion.sov=DMARC1; p=reject; rua=mailto:dmarc@notion.so; fo=1
-
P3
Publish MTA-STS (record and policy file)
Tells sending servers to require TLS to your MX hosts, which prevents downgrade attacks. The TXT record alone does nothing: the policy file must be served over HTTPS at mta-sts.notion.so. Start in testing mode, watch TLS-RPT, then switch to enforce.
Publish at_mta-sts.notion.so and https://mta-sts.notion.so/.well-known/mta-sts.txtTXT v=STSv1; id=2026100401 mta-sts.txt: version: STSv1 mode: testing mx: <your MX host> max_age: 86400
-
P3
Publish TLS-RPT
You get a report when TLS delivery to your domain fails; this is what notices a downgrade that MTA-STS is meant to prevent. The address must exist.
Publish at_smtp._tls.notion.sov=TLSRPTv1; rua=mailto:tls-rpt@notion.so
-
P3
Sign the zone with DNSSEC
Protects every record in this report from being swapped in transit. Two steps: enable signing at your DNS host (one switch at Cloudflare and most others), then add the DS record it gives you at your registrar.
Publish atnotion.so
Appendix · Raw DNS answers
| Name | Type | Answer |
|---|---|---|
| notion.so | MX | no record |
| notion.so | A | 208.103.161.17 208.103.161.2 208.103.161.1 208.103.161.16 |
| notion.so | TXT | v=spf1 ~all (+ 7 other TXT records: site-verification tokens and the like, omitted) |
| _dmarc.notion.so | TXT | v=DMARC1; p=quarantine; pct=100; rua=mailto:re+1b3a27dd30bc@inbound.dmarcdigests.com; |
| <selector>._domainkey.notion.so | TXT | cf2024-1 → key published |
| _mta-sts.notion.so | TXT | no record |
| _smtp._tls.notion.so | TXT | no record |
| default._bimi.notion.so | TXT | v=BIMI1; l=https://vmc.digicert.com/ae66f82a-dd47-4f08-9fd9-fd865f1d0b30.svg; a=https://vmc.digicert.com/ae66f82a-dd47-4f08-9fd9-fd865f1d0b30.pem |