Steps to reproduce:

1. In a Test page, add an attachment, says Attachment-A.
2. Make some modification to Attachment-A .
3. Re-attach Attachment-A to the same Test page. You should now have two versions of the Attachment-A in the Attachments tab .
4. Export Space to HTML format.
5. Open the generated Test.html page and view the "Attachments" section at the bottom of the page
6. You will notice that "Attachment-A" is listed twice with URL links to the file attachment, but both URLs link to the same exact file. (in fact it should be different)