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ThreatEmail headers

Malformed Message-ID header (RFC 5322 violation)

malformed-message-id-header

What this tier means

High-confidence threat indicator — phishing, impersonation, BEC, or scam pattern. Strong contributor to the trash decision.

How Gorganizer detects this

RFC 5322 §3.6.4 requires Message-ID headers to follow the format <local-part@domain>. Every legitimate MTA (Gmail, Outlook, SendGrid, Mailchimp) produces a well-formed ID. Fires when: (1) Message-ID contains non-ASCII characters, (2) Message-ID exceeds 255 characters, (3) Message-ID is missing the required angle-bracket+at-sign RFC structure, or (4) both Message-ID and In-Reply-To are absent (orphaned email with no provenance). Score: +2 trash.

False-positive guard

Every signal in Gorganizer feeds a multi-module score — never a sole verdict. This is a threat-tier signal — it adds a strong contribution to the trash score. The full pipeline still requires convergence across multiple modules + a margin over the safety floor before deletion happens, and Gmail's trash (30-day recovery) is always used — never permanent delete.

About the scoring engine

Gorganizer's scoring engine emits over 1,800 signals across six modules — headers, sender, subject, body, attachments, and structural metadata. Every email is scored by every module independently; the final verdict requires multiple modules to agree and the trash score to beat the safety floor by a margin.

Sacred safety guards — never delete starred emails, replies, calendar invites, receipts/invoices, or attachments — apply unconditionally regardless of any signal.

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