envelope
The SMTP sender and recipients given with MAIL FROM and RCPT TO, like the addresses on a paper envelope. Nothing forces them to match the message's own From: and To: headers, which is how senders get forged.
The SMTP sender and recipients given with MAIL FROM and RCPT TO, like the addresses on a paper envelope. Nothing forces them to match the message's own From: and To: headers, which is how senders get forged.