### [CVE-2015-4520](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-4520) ![](https://img.shields.io/static/v1?label=Product&message=n%2Fa&color=blue) ![](https://img.shields.io/static/v1?label=Version&message=n%2Fa&color=blue) ![](https://img.shields.io/static/v1?label=Vulnerability&message=n%2Fa&color=brighgreen) ### Description Mozilla Firefox before 41.0 and Firefox ESR 38.x before 38.3 allow remote attackers to bypass CORS preflight protection mechanisms by leveraging (1) duplicate cache-key generation or (2) retrieval of a value from an incorrect HTTP Access-Control-* response header. ### POC #### Reference - http://www.oracle.com/technetwork/topics/security/bulletinapr2016-2952098.html - http://www.oracle.com/technetwork/topics/security/linuxbulletinoct2015-2719645.html #### Github No PoCs found on GitHub currently.