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.
This is hardly a back door. The lemmy devs just screwed up.
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.
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.
You must not understand how open source works
Well he absolutely must learn how open source works.
But he doesn’t understand how it works.
(Sorry for the correction…)