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.

  • philm
    link
    fedilink
    arrow-up
    2
    ·
    1 year ago

    Sorry, but I start to believe that you’re not actually a(n experienced) software engineer with open source experience. The codebase isn’t that big and complex, though admittedly it’s big enough that I haven’t checked every detail yet, but again, I’m by far not the only person that watches, reads, reasons and audits the code, and that’s what makes open source so secure. Btw. I can absolutely reason about code I’m reading, I’m not exactly sure what you mean with auditing, but for me that is reading and understanding what the code does…

    The bigger the system gets the more valuable it is a target

    Well the bigger an open source project gets, the more contributors (not always, but definitely in this case) have insight into the codebase and more likely see malicious intent. So in that regard: it will get safer over time.

    • bioemerl@kbin.social
      link
      fedilink
      arrow-up
      1
      arrow-down
      2
      ·
      1 year ago

      So in that regard: it will get safer over time.

      That’s true, but it’ll never be “safe” thanks to the malicious actors controlling pull request and being easily able to bypass most eyeballs with minor or major changes.

      • philm
        link
        fedilink
        arrow-up
        2
        ·
        1 year ago

        The world will never be safe… (increasingly accelerated by climate change). The point that the devs are malicious actors still has to be proven, and I don’t see any evidence yet. They have their own instance that they control and censor/moderate (and openly so btw.), I’m totally fine with that, but the open source project certainly doesn’t have the intent to be malicious (well to some regard in taking reddits userbase ^^).

        Anyway I’m not continuing feeding the troll, have a nice day and please don’t fall to conspiracy theories (believing that the lemmy devs are malicious actors is probably the first step in that direction…)

        • bioemerl@kbin.social
          link
          fedilink
          arrow-up
          1
          arrow-down
          3
          ·
          1 year ago

          The world will never be safe… (increasingly accelerated by climate change)

          Alright, with this wild tangent I’m done here.

          • philm
            link
            fedilink
            arrow-up
            1
            ·
            1 year ago

            Ahh I just hit a wound. Just checked your history, of course how could I not see it, a climate-change denier as well, had to be… Well so you’re probably already lost then…

            • bioemerl@kbin.social
              link
              fedilink
              arrow-up
              1
              ·
              1 year ago

              Guy, climate change is an obvious and currently happening thing that I 100 percent believe is real and needs to be handled.

              Going on wild tangents about how climate change makes everyone not save in a discussion about software security is the problem.