+all
The SPF ending that returns pass for every IP address on the internet, authorizing anyone to send mail for the domain.
What it means
+all (or a bare all, since + is the default qualifier) makes every address a permitted sender. The record then authorizes nothing in particular and lets anyone pass SPF for the domain, including spammers forging it. If DMARC alignment rests on that pass, forged mail can pass DMARC too.
It is almost always a mistake, often a quick attempt to stop SPF failures, and should be replaced by the real list of sources with ~all or -all at the end.
Gmail defers or blocks mail when it finds suspicious entries in a domain's SPF record, and the error code wiki lists the codes it sends.
Example
v=spf1 +allRelated terms
On this site
Sources
What this definition rests on. The wording is ours; the facts are theirs.
- RFC 7208: Sender Policy Framework (SPF), section 4.6.2rfc-editor.org
- RFC 7208: Sender Policy Framework (SPF), section 5.1rfc-editor.org
All 432 terms in the glossaryThe wiki: blocklists and bounce codes