Microsoft Internet Explorer 7 through 11 allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption) via a crafted web site, aka "Memory Corruption Vulnerability," as exploited in the wild in August 2015.
https://docs.microsoft.com/en-us/security-updates/securitybulletins/2015/ms15-093
http://www.securityweek.com/microsoft-issues-emergency-patch-critical-ie-flaw-exploited-wild
http://www.securitytracker.com/id/1033317
http://www.securityfocus.com/bid/76403
http://twitter.com/Laughing_Mantis/statuses/633839771865886721
http://twitter.com/Laughing_Mantis/statuses/633839231840841728