CMS Sidebar - Attachment thumbnails?

[GCC LLC]

Does anyone have any ideas as to how I could go about putting thumbnails of an image attachment from a CMS article next to its' corresponding title/short description in the CMS sidebar widget on my main forum? Currently, it is displaying the avatar of the user who posted the CMS article. I know which templates, etc. to look in - I just cannot for the life of me figure out the proper code/variable/etc. to use for the img src. I have tried {vb:raw article.previewimage}, etc. without avail.

Any thoughts are appreciated, even if it's just ideas to try. Thanks in advance!