SpamAssassin Rule: ALL_TRUSTED
Standard description: Passed through trusted hosts only via SMTP
"Trusted" does not mean "trusted to not send spam." It means "trusted to not forge Received: headers."
If your message hits on the ALL_TRUSTED rule, that means all of the Received: headers in the message were inserted by SMTP relays you have indicated are "["TrustedRelays"]", and thus no tests of the source of the message (for example, tests against ["DNSBlocklists"]) will be performed.
The default scores for this rule can be found [http://spamassassin.apache.org/tests.html in the online list of tests].