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What does a spoofed header look like?

Spoofed headers show discrepancies between claimed and actual sender information. The From header might claim your-bank@example.com while Received headers show the message came from a completely different server.

Key indicators: Received headers showing unfamiliar servers, authentication results showing failures, mismatched **Return-Path** and From addresses, and unusual server names or IP addresses in the routing chain.

Example: From: CEO@company.com but Received: from malicious-server.evil.com, **Authentication-Results** showing **SPF** fail and **DKIM** fail. These discrepancies reveal **spoofing** to anyone examining full headers.