Spoofed sender delivered despite SPF fail due to missing DMARC

Ankit Mehta@Secvyn

•updated Sep 28, 2026•2•0•8

Detects inbound emails that have been delivered to the user's Inbox or Junk folder despite failing SPF authentication checks. The detection logic triggers when these emails also lack a valid DMARC policy (none or not available), which prevents the mail server from enforcing rejection or quarantine, allowing spoofed or unauthenticated mail to bypass standard security filters.