Hi all,

If you’re just now signing in for the first time in 12+ hours, you may just now be finding out that Lemmy World and other instances where hijacked. The hijackers had the full abilities of hijacked user, mod, and admin accounts. At this time, I am only aware of instance defacing and URL redirections to have been done by the hijackers.

If you were not forced to sign back in this morning, contact your instance admin to verify mitigations were completed on your instance.

How?

This occurred due to an XSS attack in the recently added custom emojis. Instance admins should follow the issue tracker on the LemmyNet GitHub, as well as the Matrix Chat. Post-Incident Activity is still on-going.

Currently, it is likely that just your session cookie was stolen, with instance admins being targeted specifically by checking for navAdmin, an HTML element only instance admins had. I do not believe this to affect users across instances, but I have yet to confirm this.

What happens next?

As I am not the developers or affected instance admins, I cannot make any guarantees. However, here is what you’ll likely see:

  1. Post Incident investigation continues. This will include inspecting code, posts, websites, and more used by the hijackers. An official incident writeup may occur. You should expect the following from that report:
  • Exactly what happened, when.
  • The incident response that occurred from instance admins
  • Information that might have helped resolve the issue sooner
  • Any issues that prevented successful resolution
  • What should have been done differently by admins
  • What should be improved by developers
  • What can be used to identify the next attack
  • What tools are needed to identify that information
  1. A CVE is created. This is an official alert of the issue, and notifies security experts (and enthusiasts), even those not using lemmy, about the issue.

  2. A code security audit is done. This will likely just be casual reviews by technical lemmy users. However, I will be reaching out to the Mozilla Foundation and Cure53 as they recently did an audit of Mastodon. If there is interest in an external audit of lemmy and the costs are affordable, I’ll look into crowdfunding this cost.

  • @[email protected]
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    261 year ago

    also, I cannot properly login into my lemmy.world account anymore. username/password work, but when I try to upvote it tells me i gotta be logged in. Tried apps and web.

    • 𝐘Ⓞz҉
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      141 year ago

      Clear cache of the app

      • @jennwiththesea
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        71 year ago

        For me it was cache and storage. Just cache didn’t work. (Using Liftoff)

      • @POTUS
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        41 year ago

        Thank you so much! I had the same problem but didn’t think of clearing the cache…

    • @roy_mustang76
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      111 year ago

      Try clearing cookies (or app cache, on app), that will most likely resolve the issue.

    • @Trapping5341
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      71 year ago

      I had the same problem on the liftoff app. Had to delete the account then sign back in and everything worked perfectly again. Personally I also changed my password because it made me feel better.

      • @[email protected]
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        41 year ago

        For liftoff, you can just add the same .world account again and it’ll work, it worked for me.

    • @Fireinthesky7
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      41 year ago

      I had to clear the app cache and local storage before it would work. Cache alone didn’t work.

    • @Alkider
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      21 year ago

      sometimes just logging in again works. if you have it set to automatically log in, that happens sometimes.