Images posted within the last 48 hours will appear as broken. This is expected and intended.
Yesterday 2023-08-27 a community on the lemmy.world instance received multiple posts containing CSAM (or as it is more commonly known CP) content, which spread throughout the federation. We also ended up becoming involuntary hosts of said content.
Due to the severely limited nature of the Lemmy moderation tools, removing or purging the incriminated posts from the admin UI wasn’t sufficient and didn’t cause the images to be actually removed from our server. Because of this, a nuclear option was required. I have deleted every image saved by our server during the last 48 hours.
Unfortunately this also includes a post on !pcm@lemmy.basedcount.com , as well as multiple posts on !returntomonke@lemmy.basedcount.com. Authors of the affected posts can fix them by re-uploading their images, without the need to recreate the posts.
We are sorry for the inconvenience, but hosting CSAM content is highly illegal and we simply can’t take any risks on this front.
I am currently discussing with the other admins whether further measures are necessary, to prevent this from happening in the future. We’ll keep you posted if we have any updates.
EDIT [2023-08-28 10:00 UTC]:
The attack is still ongoing. I have now blocked the community and further deleted the last 15 minutes of images.
For federated purges, would it make sense for a purging instance to send an automated notice of contaminated content to all federated instances? Then admins can set whether they want to handle it manually or automatically?
But it seems like it should be possible to purge recent posts only from a particular instance only.
Yes, it does make a lot of sense. But given the current state of Lemmy I doubt we can expect such a high degree of interactivity on the admin side. I think we will more likely get a dumb checkbox that, when ticked, will automatically purge the content without asking for an admin’s opinion.
And hell, after this, I would tick it without thinking twice.
I would too if i were you. But at least that way if people are abusing the feature there would be the option to prevent it. Is the developement discussion for lemmy here on lemmy or on git?
This is exactly the sort of thing that the centralized services could use to try to stop federation; smooth handling of this shit ought to be a developement priority.
I’d say the bulk of the discussion happens in github issues. There’s also a matrix room dedicated to the development of Lemmy but it hasn’t received much traffic lately.