DMARC finding

Subdomains unprotected by DMARC

The subdomain policy is weaker than the domain policy, and an attacker picks the subdomain.

Finding code

dmarc_subdomains_unprotected

This finding appears in the findings array of the spam checker and the POST /v1/sender API response when the condition above is detected.

How to fix it

The fix.

Add sp=reject (or match the domain policy) so subdomains are protected. An attacker who cannot spoof the domain will try a subdomain instead.

Related DMARC findings

Other things we check.

Finding What it means
dmarc_missing No DMARC record
dmarc_multiple_records Multiple DMARC records
dmarc_syntax_error DMARC syntax error
dmarc_monitoring_only DMARC monitoring only
dmarc_quarantine_only DMARC quarantine only
dmarc_partial_coverage DMARC partial coverage
dmarc_no_aggregate_reports No DMARC aggregate reports