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Is your SPF record broken or too permissive?

By Mark KashefPublished October 8, 2026

The broken SPF check finds SPF setups that mail servers cannot rely on, such as two records at once, a record that lets any sender pass, or one that needs more DNS lookups than mail servers allow.

What does this check look at?

It looks at whether your SPF setup is duplicated, allows any sender, or needs more DNS lookups than mail servers allow. Others list too many services in SPF and break the limit on lookups, so the record stops working.

Pulse and Deep scans both run it. It reads public records about your domain and never touches your site.

Curious what your site shows from outside? The quick check is free and needs no account.

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What does a result mean?

What the report showsWhat it meansWhat to do
Medium findingThe record lets any sender pass.End it with a soft fail or a hard fail instead.
Low findingThere are two records, or too many lookups.Merge into one record and trim the includes.

It does not check whether your real senders are listed. A clean result means nothing was found in what the scan read. It does not prove the problem is absent from parts the scan never sees.

How serious is a finding?

Treat this as a hardening gap. It makes an attacker’s job easier but gives them no path of its own, so fix it after anything more direct. Confidence starts at medium, because it rests on public records rather than a response from your site. The report lists what to fix by how directly someone could use it, not by the severity label.

What does a confirmed finding have to show?

PartFor this check
Where it startsMail servers checking who may send for your domain
The protection that should stop itThe SPF record is invalid, permissive or over the lookup limit
What is reachedSPF errors or lets any sender pass
What followsWeaker email authentication for your domain

Which standards does it relate to?

StandardReference
OWASP Top TenA02:2025 Security Misconfiguration
CWECWE-345

Each one is a related control, not a verification. A scan sees what anyone online can see, so it never proves a whole requirement is met.

Fix it with your AI

The usual repair is merging duplicates and removing includes for tools you no longer use.

Fix prompt for any coding agent
My SPF record is broken: [paste the evidence from the report]. Read my current SPF TXT records, list every include and what service it belongs to, and ask me which of those services still send mail as my domain. Then write one replacement v=spf1 record that covers only those, stays at or under ten DNS lookups when expanded, and ends in ~all. Tell me which old records to delete.

How to check

Say Atlas, our example app at atlas.example, added a second SPF record for a new newsletter tool instead of editing the first. Mail servers treat two records as an error, and the check names it.

Run a Pulse scan from your Lockpick account to see it for your site. Pulse or Deep explains what each scan reads, and the full list of checks shows the rest.

Questions people ask

Why is two SPF records worse than one?

Mail servers treat more than one SPF record as an error, so neither one counts and your mail loses its SPF pass.

How do I get under the lookup limit?

Remove includes for services you no longer use, and ask providers for a narrower include. Some teams use a flattening service, which needs upkeep.

See what your site shows from outside

A quick check reads your homepage the way a visitor would and gives you a score. No account needed.

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Related pages

  • Does your domain publish an SPF record that refuses unknown senders?
  • Can anyone send email that looks like it came from your domain?
  • Would you find out if someone faked email from your domain?

Sources

  1. Email anyone can send Lockpick docs, read on October 7, 2026
  2. How we rate findings Lockpick docs, read on October 7, 2026

About the author

Mark Kashef, Founder of Lockpick

I'm Mark, and I build Lockpick. I write these pages, and each one is checked against its sources before it goes live. The Updated date changes only when the page itself does.

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Lockpick is a security scanner for vibe-coded apps. It checks what your live site exposes and what a GitHub repo or AI skill would do before you install it, then gives you a fix prompt for Lovable, Bolt, Replit, Cursor or Claude Code.

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