While I was asleep, apparently the site was hacked. Luckily, (big) part of the lemmy.world team is in US, and some early birds in EU also helped mitigate this.

As I am told, this was the issue:

  • There is an vulnerability which was exploited
  • Several people had their JWT cookies leaked, including at least one admin
  • Attackers started changing site settings and posting fake announcements etc

Our mitigations:

  • We removed the vulnerability
  • Deleted all comments and private messages that contained the exploit
  • Rotated JWT secret which invalidated all existing cookies

The vulnerability will be fixed by the Lemmy devs.

Details of the vulnerability are here

Many thanks for all that helped, and sorry for any inconvenience caused!

Update While we believe the admins accounts were what they were after, it could be that other users accounts were compromised. Your cookie could have been ‘stolen’ and the hacker could have had access to your account, creating posts and comments under your name, and accessing/changing your settings (which shows your e-mail).

For this, you would have had to be using lemmy.world at that time, and load a page that had the vulnerability in it.

  • RuudOPMA
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    9110 months ago

    Good point, I’ll update the post.

    • Vamp
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      5010 months ago

      Also I am curious, what’s the easiest way to currently reach the admins in case this happens again somehow? Two of them on their account have been seemingly inactive for a month and as per your own statement you rarely check your notifications and dms. Is there a discord somewhere for it?

    • BustedPancake
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      2010 months ago

      So all our cookies are negated now with the JWT changed, and we just needed to login again? Can attackers have stolen our cookies in order to use our accounts to post as if it was us? I’m sure they were only interested in admin cookies, so most others were “useless” to them? I see nothing wrong with my posts so I should be safe, right?

      • @cantevencode
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        2610 months ago

        Prior to the JWT secret being rotated, yes, they could have authenticated as you. The tokens are now all invalid and useless

      • Vamp
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        910 months ago

        Probably. I had to re-login myself.

      • @RookiA
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        510 months ago

        If you think they could change your password:

        YES, they could.

        They could have changed the email => “Forgot PW” and with that you lost ur account.

        • Xero
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          2
          edit-2
          10 months ago

          I think I’ve lost my account, I clicked Forgot Password and nothing came into my mailbox. This account is the one I made just now.

          My old account:

          If you see that account post or comment on anything, please report it

          Edit: Nvm, I use another email to sign up for Lemmy and forgot about it

          • @RookiA
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            310 months ago

            Report it directly to Ruud or otherwise he will just delete it.

            • Xero
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              510 months ago

              actually nevermind, I forgot that I use a different email for Lemmy, I can log back in now

              • @TheSmartDude
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                edit-2
                10 months ago

                It happens to all of us. Additionally, assuming that you’ve come here recently, there’s not much data on it, and it being deleted will not be that much of a big deal.

    • @InverseParallax
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      1610 months ago

      Nice work on the recovery, especially from a 0-day.

      • @[email protected]
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        fedilink
        2410 months ago

        They defaced it with dicks and changed the federation list to be only threads.net. I don’t think it was a state sponsored chinese hacking group. :)

        • @linearchaos
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          1710 months ago

          I’m ok with the dicks but the threads are TOO FAR!!! shuffles off to the angry done**

          Thank you all for staying on top of it.

        • Milan
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          fedilink
          410 months ago

          right after the update we also had most of the serverlist cleared except threads.net (which was the last one added so i assumed it was some bug) – otherwise nothing appears to be touched on this instance tho.