hydrogen.cc in Google V8, as used Google Chrome before 40.0.2214.91, does not properly handle arrays with holes, which allows remote attackers to cause a denial of service (memory corruption) or possibly have unspecified other impact via crafted JavaScript code that triggers an array copy.
https://codereview.chromium.org/737383002
https://code.google.com/p/chromium/issues/detail?id=435073
http://www.ubuntu.com/usn/USN-2476-1
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/62575
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