When receiving post content via incoming email a new image is downloaded each time and stored.
Steps to reproduce
- Setup email to be received by group in a shared inbox
- you receive an email from PayPal links their logo:
- Discourse downloads said logo and keeps a copy.
- Wait for micro-payments to roll in.
- Lucky you now receive 1000 emails in a single day from PayPal.
- a single copy of the logo to be stored on disk.
- Lucky you, you now have 1000+ copies of their logo.