Loren, See https://tools.ietf.org/html/rfc6648 but basically for email think of X- as local headers, 100% allowed, do whatever you want with them, no one should pay any attention unless you publish what they mean. Lots of places, my firm included, add X-* headers for various purposes.
Regards, KAM -- Kevin A. McGrail Member, Apache Software Foundation Chair Emeritus Apache SpamAssassin Project https://www.linkedin.com/in/kmcgrail - 703.798.0171 On Sun, Mar 28, 2021 at 11:08 PM Loren Wilton <[email protected]> wrote: > I've started seeing a number of spams with the following block of X > headers > in it. I've never seen these before. While these look really fake to me > (from the content of most of them), does any real tool or site make > headers > like this, or are they just from some spam tool and I can use them as a > guarantee of spam? > > x-mcpf-jobid: mc.us6_13712451.1216993.5a2d921a72084.full_000003 > X-MC-User: 6b669534c4be2b401d8744486 > X-MC-Tags:45829 > X-MC-Track:456 > X-MC-Autotext:global > X-MC-AutoHtml: format > X-MC-Template: smiley > X-MC-MergeVars: {"_rcpt": "[email protected]", "fname": "John", > "lname":"Smith"} > X-MC-GM-Analytics: normal > X-MC-GoogleAnalyticsCampaign: good > X-MC-Metadata: { "user_id": "45829", "location_id": "111" } > X-MC-URLStripQS: link to <AsianBeauties Team> > X-MC-PreserveRecipients: 123 > X-MC-InlineCSS: used > X-MC-Subaccount: sendgrid > X-MC-ViewContentLink: {uurl} > X-MC-BccAddress: {ourl} > X-MC-Important: notes > X-MC-IpPool: 99% > X-MC-ReturnPathDomain: server1.tech > X-MC-SendAt: "AsianBeauties Team" > X-MC-MergeLanguage: {all language} > X-MC-MergeVars: {"var1": "global value 1"} > X-MC-MergeVars: {"_rcpt": "[email protected]", "fname": "John", > "lname":"Smith"} > X-MC-GoogleAnalytics: www.domain.com, domain. > X-MC-Metadata: { "user_id": "45829", "location_id": "111" } > X-MC-Metadata: { "group_id": "users_active" } > X-MC-Metadata: { "_rcpt": "[email protected]", "user_id": "123" } > X-MC-Metadata: { "_rcpt": "[email protected]", "user_id": "456" } > x-mcda: TRUE > > >
