There have been users spamming CSAM content in !lemmyshitpost@lemmy.world 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.
Update
Apparently the Lemmy Shitpost community is shut down as of now.
Was going to say the same. Windows and Linux both use “lazy” ways of deleting things, because there’s not usually a need to actually wipe the data. Overwriting the data takes a lot more time, and on an SSD it costs valuable write cycles. Instead, it simply marks the space as usable again, and removes any associations to the file that the OS had. But the data still exists on the drive, because it’s simply been marked as writeable again.
There are plenty of programs that will be able to read that “deleted” content, because (again) it still exists on the drive. If you just deleted it and haven’t used the drive a lot since then, it’s entirely possible that the data hasn’t been overwritten yet.
You need a form of secure delete, which doesn’t just mark the space is usable. A secure delete will overwrite the data with junk data. Essentially white noise 1’s and 0’s, so the data is completely gone instead of simply being marked as writeable.
Would rm be okay if you regularly fstrim?
From: https://en.m.wikipedia.org/wiki/Trim_(computing)#Operation
So: probably yes.