cross-posted from: https://sh.itjust.works/post/923025
lemmy.world is a victim of an XSS attack right now and the hacker simply injected a JavaScript redirection into the sidebar.
It appears the Lemmy backend does not escape HTML in the main sidebar. Not sure if this is also true for community sidebars.
This has nothing to do with XSS, it is a simple HTML injection vulnerability, and it can only be exploited by instance admins.
Also Lemmy.world appears to have been running a custom frontend so it’s hard to say how widespread the affects of this are.
You seem to be following the situation closely. Could you please DM me on Matrix?
Worst case scenario, they can steal your Lemmy session, right?
Which isn’t super bad for a service like Lemmy. This isn’t a social network, so most contact list scams would be useless.
Edit: just read the targets were admins. That IS bad.
Lemmy isn’t a social network? Seems to be one to me.
I mean, not in the traditional sense. You don’t have your family and friends as Lemmy contacts and share posts with them. It’s more anonymous.
It seems to have just gotten to Lemmy.blahaj.zone
I wonder if there is something the Lemmy.ca admins can do to disable the sidebar or put a workaround in to prevent this.
At this point I’m monitoring inter-instance communications channels non stop even though I should be in bed. I will be temporarily removing admins that have not responded to my inquiry to confirm if they have 2FA authentication turned on as initial access appears to have been gained due to lack of 2FA.
If there’s anything additinal we can do, we will.
Good luck, and thanks for all your hard work. I don’t know if you already saw this, but it looks like this might be the vector for the account compromise. If that’s the case, I don’t think 2FA is enough to protect, because it’s exfiltrating the session cookies of someone already logged in. Seems like the precaution is for admins to avoid clicking any suspicious links. I realize the irony of sharing a link about this, but at least it’s to a thread on this instance.
I’m copying all links into a brand new incognito mode window for now.
Removed by mod
There’s no minimum complexity but I’ve enforced 2FA for all admins. One admin that did not respond has been temporarily removed precautionarily.
thanks for your hard work, even though i am sure you’re tired as hell. i think that person’s idea about a minimum complexity requirement in addition to 2FA is a good idea, perhaps something like a complex password generator like LastPass or something, anything.
We can put it in place as a internal policy. I’m 99% confident all admins on Lemmy.ca are using complex password generators, that are hopefully not LastPass with their history of being hacked 😅
Edit: yeah I’m tired. It’s like 3 hours post bed time. I’m supposed to be at work in just over 5 hours.
I’m supposed to be at work in just over 5 hours.
shit that sucks. this happened at a bad time, i’m sorry. are their people besides you who are keeping an eye on this and maintaining it, for when you go off to work or when you need to sleep? cause everyone needs their sleep
I mean, if it’s something that’s editable only by admins of the instance, I’m not sure it constitutes a vulnerability, since admins can change the content to whatever they desire by definition.
Wasn’t clear till further people commented that it was something only and admin could do. So I agree.
We have yet to confirm if a vulnerability exists in the sidebars that can be set by community mods.
can you temporally take away the ability for mods to put html or any kinda script into the sidebar, at least for now?
That would essentially be patching the vulnerability. A temporary fix would be just preventing the sidebar from being editable.
(Ideally the vulnerability would be patched, but these things take time.)
No. Unfortunately. This is not a confirmed vector of attack at this point but we are monitoring.
for some reason I had to reset my password.
deleted by creator
