spf.single_record Reviewed July 2026

Quick fix

Export every current SPF value and identify all unique authorized senders.

What this finding means

SPF requires one effective `v=spf1` record per DNS name. SecuTest flags multiple records because receivers must treat that state as `permerror`; they do not merge the records automatically.

Interpretation boundary Use the exact evidence in your report. SecuTest reports externally observable conditions; it does not assume ownership, exploitability, compromise, or business intent when those cannot be proven remotely.

Associated attack or threat scenario

Threat type SPF authentication failure and spoofing opportunity

How the attack or failure scenario works

A permanent SPF error means the receiver cannot evaluate the domain's sender authorization policy. Depending on the receiver and DMARC state, legitimate mail may be rejected while forged mail loses an expected negative signal. The condition is caused by configuration, not by an attacker directly bypassing SPF.

Conditions and limitations

  • Two or more logical `v=spf1` TXT records are published at the same owner name.
  • The receiver follows RFC-compliant SPF processing and returns `permerror`.
  • Abuse impact increases when DMARC relies on SPF alignment and DKIM is absent or misaligned.

Why it matters

Security and business impact Publishing multiple SPF records causes a permanent SPF error, disabling reliable sender authorization and potentially harming delivery.

Step-by-step fix

Where to make the change

  • The authoritative DNS zone for the registrable domain.
  • The outbound or inbound mail platform when sender authorization, signing, or routing is involved.
  • The DMARC reporting mailbox or reporting service when aggregate reports are required.

Remediation procedure

  1. Export every current SPF value and identify all unique authorized senders.
  2. Merge mechanisms into one syntactically valid record, preserving only required sources.
  3. Remove all duplicate SPF TXT records from the authoritative DNS provider.
  4. Validate the merged record's lookup count and test each legitimate sender before lowering the TTL or enforcing `-all`.

Commands and configuration examples

Replace example values with the hostname, selector, IP address, port, provider, or policy values shown in your SecuTest evidence. Review every example before production use.

Find duplicate SPF records
dig +short TXT example.com | grep -i 'v=spf1'

Merged provider example
example.com. 3600 IN TXT "v=spf1 include:spf.protection.outlook.com include:_spf.example-saas.net -all"

Verify the fix

  1. Query multiple public resolvers and confirm exactly one `v=spf1` value is returned.
  2. Count recursive DNS lookups and keep the evaluation at ten or fewer.
  3. Send messages from each authorized platform and confirm `spf=pass`.
  4. Review DMARC reports for new SPF failures after the change.
Confirm the externally visible result

After DNS, CDN, certificate, mail, or application propagation completes, run a fresh SecuTest scan and compare the new evidence with the original finding.

Re-scan your domain

Common mistakes

  • Concatenating two full records and leaving a second `v=spf1` token in the middle.
  • Deleting a record before incorporating the sender it authorized.
  • Confusing TXT string fragments returned by DNS with separate logical records.

Authoritative references