There have been users spamming CSAM content in [email protected] causing it to federate to other instances. If your instance is subscribed to this community, you should take action to rectify it immediately. I recommend performing a hard delete via command line on the server.
I deleted every image from the past 24 hours personally, using the following command: sudo find /srv/lemmy/example.com/volumes/pictrs/files -type f -ctime -1 -exec shred {} \;
Note: Your local jurisdiction may impose a duty to report or other obligations. Check with these, but always prioritize ensuring that the content does not continue to be served.
Naive question here: would it be valuable to generate hashes of those images and provide them as a public database? Seems like it would be valuable to reject known images using some mechanism to prevent this from happening broadly. It wouldn’t stop someone from on-the-fly systematically editing/saving/uploading CSAM, but hashes are cheap to store and it would at least provide one barrier to entry.