Drawing attention on this instance so Admins are aware and can address the propagating exploit.

EDIT: Found more info about the patch.

A more thorough recap of the issue.

GitHub PR fixing the bug: https://github.com/LemmyNet/lemmy-ui/pull/1897/files

If your instance has custom emojis defined, this is exploitable everywhere Markdown is available. It is NOT restricted to admins, but can be used to steal an admin’s JWT, which then lets the attacker get into that admin’s account which can then spread the exploit further by putting it somewhere where it’s rendered on every single page and then deface the site.

If your instance doesn’t have any custom emojis, you are safe, the exploit requires custom emojis to trigger the bad code branch.

  • tal
    link
    fedilink
    251 year ago

    And this is why you don’t trust tankies. It’s very easy to compromise the software and put back doors into it.

    This is hardly a back door. The lemmy devs just screwed up.

    Use kbin instead.

    Kbin had a fix for an SQL injection exploit the other week. Both probably still have security holes that haven’t yet been identified.

    There are more eyes on the software as the userbase grows, and people are going to find more flaws. That’s just the way things go.

    • bioemerl
      link
      fedilink
      -181 year ago

      This is hardly a back door.

      I literally said it wasn’t in my comment, it’s evidence of how easy it is to put one in down the line despite the fact this is open source software.