The same-origin-policy is one of several models that web browsers use to determine which JavaScript files in a webpage should be executed. This is determined by the domain (the origin).

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2answers
39k views

Why is the Access-Control-Allow-Origin header necessary?

I understand the purpose of the Access-Control-Allow-Credentials header, but can't see what problem the Access-Control-Allow-Origin header solves. More precisely, it's easy to see how, if ...
41
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4answers
13k views

Why is the same origin policy so important?

I can't really fully understand what same origin domain means. I know it means that when getting a resource from another domain (say a JS file) it will run from the context of the domain that serves ...
10
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2answers
4k views

Using iframes to sandbox untrusted code

I'm trying to create an extensible platform, where my site will provide a model and some views (both client-side, in the browser) and third party sites may add their own views as well. The goal here ...
9
votes
2answers
614 views

User-specific Subdomains : JavaScript security

If I provide a public-facing website for users on my website at their own subdomain (e.g. bob.myapp.com) under their own control, can I allow them to execute arbitrary JavaScript without putting my ...
5
votes
1answer
619 views

Child iFrame hash verification of parent iFrame content

Consider the following scenario: Alice wishes to browse Victor's website while on the job at Initech. Victor's website is hosted on an alternative domain name system to which Initech's DNS does not ...
3
votes
3answers
590 views

Flash ignores Content-Type header, allowing XSS?

I recently read that the Flash plugin ignores the Content-Type header in certain circumstances. In particular, you can give Flash a URL, and the Flash plugin will happily fetch the content at that ...
5
votes
3answers
3k views

Do browsers allows pages loaded on one tab to access/intercept/inject data in other tabs?

I was surprised to hear from this Reuters video that it was possible for a page loaded on one tab to access and/or inject data onto another page loaded on a different tab. TL;DW (too lazy; didn't ...
1
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1answer
219 views

Understanding Same origin policy

I am trying to understand same origin policy better. From what I understand same origin policy restricts code from one "origin" not access data from another "origin". What I am trying to understand is ...
3
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1answer
240 views

What servers or clients are immune to related-domain cookie attacks? (*.example.com)

In this question, I want to identify browsers, servers, or implementations that are immune from related domain cookie attacks (e.g. a.example.com vs b.example.com). Lacking any tangible solution, ...
17
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5answers
2k views

What is the point of the same-domain rule for xmlhttprequest when script tags/JSONP can cross domains?

I get that I don't want a page loaded from stackoverflow.com to be able to request gmail.com on my behalf and read my email--but this seems to be simply a cookie issue. Since JSONP bypasses ...
7
votes
4answers
182 views

Same-origin policy for desktop application?

The same-origin policy is one of the most important security feature in our browser. It basically provides sandboxing for our applications which is protecting our users. Desktop application can read ...
4
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1answer
693 views

Does returning `Access-Control-Allow-Origin: *` weaken the security of JSON GET responses?

The W3C CORS recommendation states: Certain types of resources should not attempt to specify particular authorized origins, but instead either deny or allow all origins. ... 3. A GET ...
3
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1answer
696 views

Access-Control-Allow-Origin wihout AJAX

The post at http://security.stackexchange.com/a/43456/8340 (incorrectly?) states No, as long as the CORS Access-Control-Allow-Origin is at its default restrictive value. This prevents the outer ...