Lemmy security vulnerability update

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https://feddit.uk/post/453040

So last night a XSS scripting attack was found on all Lemmy instances. See the lemmy world update here https://feddit.uk/post/453040

What this means is that hackers could inject their own "script" when any user viewed a comment/post that the hackers made. The hackers would then grab your JWT token with the script so they could impersonate that user. (And perform any actions on behalf of the user)

Luckily, it looks like I haven't been compromised so the site config should all be the same

What has been done about this

I've removed any comments or posts which included the script see here https://github.com/LemmyNet/lemmy-ui/issues/1895

I would have removed all custom emojis as well but there was none in our DB, this may potentially mean that this site was not affected. Just in case, I've also rotated the JWT tokens so all tokens are now invalid. This means you will have to logout and log back into the instance

Shoutout to @clara@feddit.uk for messaging me about this and bringing it to my attention

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Thanks for doing this, sounds like people were on the ball and managed to sort it quickly.

I imagine the code will be probed quite a bit and this won't be the last time, the important thing is to move fast and sort it out.

Thanks for jumping on this so quickly! And all work you're doing to support this new platform!!

Thank you for your concern and the detailed update!

Thanks Tom and Clara.

Cool! Thanks Tom, appreciate the update and the speedy response.

Great job!

I don't know if it's related. Since today when I login to the Jerboa app then try to post or close/reopen the app my account for feddit.uk disappears from the app. I have to keep logging in.

You may need to clear the cache and data for Jerboa on your phone first, then log back in.

Thanks for the tip. I just tried that, didn't work. So I then I deleted all data and that did! It meant I had to login to all my accounts again but it seems to be working.

Just to say, mine seems ok after closing and reopening the app... but I'll check again later.

Same issue for me. Also using Jerboa.

Might not be related but after signing out I’ve not been able to sign back in to app.feddit.uk - using vger.app works fine though.

I think Tom.said that it breaks every time there's an update.

I just saw his post about doing an update - it’s let me in now

I've been able to sign into the generic wefwef webapp so unsure if there is a difference with the Feddit version.

Thanks for keeping us all safe.. :)

I got a connection error trying to use your wefwef instance. Is this related to the update?

https://app.feddit.uk

Yeh fixed and fixed the issue where updating broke it so that shouldn't happen anymore

Ty for acting, however I cannot seem to log in on Jerboa. It shows me all of my subscribed feeds but then won't let me comment. Closing and reopening the app logs me out again

You may need to clear the cache and data for Jerboa on your phone first, then log back in. I was having the same issue, but that seemed to fix it for me.

Yep, fixed it for me also

Thanks for keeping us all safe.. :)

glad you managed to protect our instance before anything bad happened, good job 🥳 i was worried i'd wake up to a rather spicy looking front page lol. thanks for the hard work!