A malicious site will load your site in an iframe, fill in your form and post it. Fixing it requires some a token in your form, but I can see you don't understand how an extra hidden field in your form will make a difference so you're clearly not going to handle it correctly. You're screwed. Go home.
As far as I can tell, CSRF should have existed since javascript & frames. How have the browser vendors not fixed such a huge insecure-by-design flaw?
Pages making GET requests across domains is so common and necessary that several technology standards would have to come together to propose a real fix. Every image or script loaded from a CDN. Anyone hosting their own static assets domains. Anyone using a plugin from Google, Facebook, Twitter, Disqus uses this ability.
The tech companies can't even easily create a system to whitelist sites allowed to embed them, because that would severely limit third party's ability to use their services freely and would introduce a huge performance bottleneck.
I haven't seen any particularly compelling solution to solving this. Things only guarded behind a GET request can be loaded by script, link, embed, object, img and iframe tags, and all of those have legitimate reasons for loading resources cross domain without requesting permissions for each one from the user.
I don't want the legitimate uses prevented. The default behavior should be to prevent, and the legitimate uses should explicitly opt-in. That way, you only have to do security analysis for those explicit points.
This to me is a server side issue- but that doesn't necessarily mean it's on the app developer. The behavior you're talking about can be set most servers directly, by adding the "X-Frame-Options" header into every request by default. Then exceptions would have to be made explicitly, by either the server admin or application developer. If anyone should change the default behavior (which I am not convinced is the case) it should be the server developers, not the browsers.
CSRF is solved very simply by using tokens for each field. If the attacking site can't load the other page, it can't pull the token out, and without the token the post gets discarded. If you've abstracted your form generation this should be super simple to add.
Why shouldn't you trust user-provided data to secure the same user's data? The potential attack is someone forging their own referer header in order to attack themself.
A malicious site will load your site in an iframe, fill in your form and post it.
I browser cannot do this. The OP probably saw some exploit code in an ad which was served in an IFrame, but the same-domain security model will not allow you to interact with another window or IFrame that is of a different domain.
Here's my take away from every CSRF article:
A malicious site will load your site in an iframe, fill in your form and post it. Fixing it requires some a token in your form, but I can see you don't understand how an extra hidden field in your form will make a difference so you're clearly not going to handle it correctly. You're screwed. Go home.
As far as I can tell, CSRF should have existed since javascript & frames. How have the browser vendors not fixed such a huge insecure-by-design flaw?