Way OT: interesting spam

Every now and then I get a spam message that seems to somehow bypass my Outlook html-mail settings and show an image without me saying it’s ok to do so.

The spam has no attachment and when I “View Source” it appears that the line that loads the image is [img]cid:bUmaOivjlQG5UFtOa7UI[/img] So there’s no internet path at all for it nor is there one anyewhere in the mail.

Photoshop will only open the image if it has a .bmp extension.

Does anyone know how this is done?

the image is embedded in the email code, just like an attachment. The cid allows the attachment to be displayed in the email.