Google Chrome before 40.0.2214.91, when the Harmony proxy in Google V8 is enabled, allows remote attackers to bypass the Same Origin Policy via crafted JavaScript code with Proxy.create and console.log calls, related to HTTP responses that lack an "X-Content-Type-Options: nosniff" header.
https://code.google.com/p/chromium/issues/detail?id=399951
http://www.securitytracker.com/id/1031623
http://www.securityfocus.com/bid/72288
http://security.gentoo.org/glsa/glsa-201502-13.xml
http://secunia.com/advisories/62665
http://secunia.com/advisories/62383
http://rhn.redhat.com/errata/RHSA-2015-0093.html
http://lists.opensuse.org/opensuse-security-announce/2015-03/msg00005.html
http://googlechromereleases.blogspot.com/2015/01/stable-update.html