Ask HN: Has CORS Solved Anything?

It's a necessity that when implemented improperly leaves a sizeable security hole.

I recently got a bug bounty for finding a CORS vulnerability and showing a proof of concept phishing site that uses all of the resources from the genuine origin. The site was accepting a wildcard origin whereas it should've used a whitelist.

All I have to do is put a proxy in front of your API and strip all your headers off and send responses anywhere I like. Given that, how can CORS be "security"? It's totally insecure.

The point here is that if you put a proxy in front of your API, on your own infrastructure, _you are no longer in origin scope_ and cookies will not be sent along with the request.

It is CORS that restricts running foreign javascripts in your page. Clearly a win