CORS requests should not follow 30x redirections after preflight — Mozilla

Mozilla developer Christoph Kerschbaumer discovered an issue while investigating Mozilla Foundation Security Advisory 2015-03, previously reported by security researcher Muneaki Nishimura. This flaw was that a cross-origin resource sharing CORS request should not follow 30x redirections after...

CVE-2013-1639

Opera before 12.13 does not send CORS preflight requests in all required cases, which allows remote attackers to bypass a CSRF protection mechanism via a crafted web site that triggers a CORS request...

CORS requests can omit the preflight request

Cross-Origin Resource Sharing CORS requests are required to send a preflight request if custom headers are included, to check that the host wishes to allow the full request to be made. An example of where this may be needed is for sites that use a custom header with a static value as part of thei...

CORS requests can omit the preflight request – Opera Security Advisories

Cross-Origin Resource Sharing CORS requests are required to send a preflight request if custom headers are included, to check that the host wishes to allow the full request to be made. An example of where this may be needed is for sites that use a custom header with a static value as part of thei...