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.
You’re still trusting code you shouldn’t.
In case you haven’t understood my previous argument. I trust code I can actually read and reason about (compared to e.g. reddit, facebook etc.). And just to prove my point, I am already looking over the codebase of lemmy, because there are obviously a lot of things that can still be improved, but malicious intent I haven’t found yet. And if I have missed something, other people will certainly find such things, and if that’s the case (which I don’t believe) then shit will certainly hit the fan.
kbin is also open source, and I’m happy that there are other projects with a similar vision as lemmy (the choice for PHP is an absolute mystery for me, but whatever floats your boat I guess). More (non-malicious) implementations always improve the fediverse in many ways.
I trust code I can actually read and reason about
Unless you’re auditing the code yourself you can’t. This is my point. The fact something is open source does not and will never protect you unless you go out of your way to do the herculean task of auditing it yourself.
And even if you audited it, guess what happens next week? Next year? The bigger the system gets the more valuable it is a target. I don’t expect anything malicious to happen now. I expect it to happen once the growth phase is over.
At the end of the day it all falls down to trust.
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.
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.
