alesian.security
← Top 100 Domains

digicert.com

Number 42 of the Top 100 · Tranco rank 48

digicert.com belongs to DigiCert, one of the largest issuers of the certificates behind HTTPS. Browsers and operating systems reach names such as ocsp.digicert.com to check that a certificate has not been revoked, so it appears in logs on any network.

Can digicert.com be forged?

Can digicert.com be forged?

Partly. Forged mail goes to the spam folder, where people still find it.

The exact name
quarantine · subdomains quarantine · reports to Valimail
Names that copy
18 registered lookalikes can send mail. DMARC never sees them. See them →

What we noticed

  • include:%{i}._ip.%{h}._ehlo.%{d}._spf.vali.email resolves for each message, so the senders it allows cannot be listed from outside.
  • The DMARC policy sends failing mail to the spam folder. A policy of reject stops it.
  • The SPF record marks an unlisted sender as a soft failure. A hard failure is stronger.
Senders it names Marketo
  • Marketo include:mktomail.com· DKIM key found
  • Microsoft 365 runs its mail hosts

These are the services the records name. A record can name a service no longer used, and a sender can sign without being named.

SPF~all · 3 of 10 lookups · at least 21 thousand addresses

Flags others · 3 of 10 lookups · 0 of 2 void lookups · 21,058 IPv4 addresses · 0 IPv6 blocks · Kept by a sender-policy service

The full list cannot be known from outside: it uses macros.

Every term and include
  • include:%{i}._ip.%{h}._ehlo.%{d}._spf.vali.email resolves for each message, so its senders cannot be listed — — 1
  • their record 21,057 — 1
  • 1 — 1
  • ~all — — —
    • DKIM6 keys found
    • m1._domainkey · rsa 1024· Marketo
    • mail._domainkey · rsa 1024
    • s1._domainkey · rsa 2048· SendGrid
    • s2._domainkey · rsa 2048· SendGrid
    • selector1._domainkey · rsa 2048· Microsoft 365
    • selector2._domainkey · rsa 1024· Microsoft 365

    We look under the selectors of the services the records name. A domain can have keys we do not find.

    Sending names 1 name, 0 at reject
    NamePolicySPF lookupsReports to
    partners.digicert.comquarantine (inherited)2—

    The first 50 names are checked.

    ReportsValimail

    Aggregate reports (rua) go to mailto:dmarc_agg@vali.email, mailto:dmarc@digicert.com. No failure reports are asked for.

    Transport MTA-STS none · TLS-RPT none · BIMI none

    MTA-STS asks senders to deliver to digicert.com over encrypted connections only. TLS-RPT asks for reports when they cannot. BIMI shows a logo beside mail that passes DMARC at quarantine or reject.

    Read on Oct 28, 2026. Check it again yourself →

    Watch your own domain's mail this way: Sender Security · the DMARC Report