WebKit/Source/core/layout/LayoutBlock.cpp in Blink, as used in Google Chrome before 49.0.2623.75, does not properly determine when anonymous block wrappers may exist, which allows remote attackers to cause a denial of service (incorrect cast and assertion failure) or possibly have unspecified other impact via crafted JavaScript code.
https://codereview.chromium.org/1423573002
https://code.google.com/p/chromium/issues/detail?id=591402
https://bugs.chromium.org/p/chromium/issues/detail?id=546849
http://www.ubuntu.com/usn/USN-2920-1
http://www.securitytracker.com/id/1035185
http://www.securityfocus.com/bid/84170
http://googlechromereleases.blogspot.com/2016/03/stable-channel-update.html