Cross-origin resource sharing

It is a massive vulnerability if you aren't paying attention.

Because the WebSocket upgrade handshake starts as a standard GET request, it completely bypasses the browser's same origin policy and standard CORS rules.

Let's unpack those terms for a second.

Standard rules usually prevent a website on one domain from reaching into another domain, right? Correct.

... which is the, the crazy thing.

The whole CORS is just bypassed.

Yeah, dude.

This is such a beautiful thing, and, uh, I'm, I'm confused as well.

in Chromium.

And so the, to continue the story, so the, we have this DNS rebinding technique that, that works, but, uh, over the past year they have actually started fixing this, uh, with a feature called Local Network Access, LNA, uh, that will...

It's, it's kind of a secondary layer of CORS, where even if you fetch a same UR- same origin URL, it'll still try and, uh, check if the IP that's behind it is the same, like, localness, uh, of the one that's requesting it.

So in our case, we have the public attacker.com-

Notably, some of these websites help agents circumvent existing control measures.

CORS proxies allow agents to circumvent blocked URLs.

Link shorteners allow agents to cache questions and answers for future models, and jQuery or JSON query splices make this problem worse.

Get-to-post converters allow models to make writes much more easily.

Go into the Python backend directory.

Check the CORS configuration headers.

Run a test request and see if it is rejecting our local frontend URL.

And what happens in my terminal window?

And what might it say?

It might say, I checked the Python backend.

The CORS headers are perfectly fine.

The issue's not here.

The backend can bump an asset's version number and issue new URLs to ensure clients don't unknowingly use a revoked file.

Another nuance is cross-origin resource sharing, CORS.

Browser-based web apps need the correct CORS headers so that audio files can be loaded into web audio contexts without headaches.

In fact, with Web Audio API, you could stream a preview directly in the browser, apply an instant effect, and give users immediate feedback about how that clip would sound when layered with their project.

When thinking of authentication again, token revocation is critical if a user subscription lapses or they violate licensing terms.