The Microsoft Malware Protection Engine running on Microsoft Forefront and Microsoft Defender on Microsoft Windows Server 2008 SP2 and R2 SP1 Windows 7 SP1 Windows 8.1 Windows Server 2012 Gold and R2 Windows RT 8.1 Windows 10 Gold 1511 1607 and 1703 and Windows Server 2016 Microsoft Exchange Server 2013 and 2016 does not properly scan a specially crafted file leading to denial of service. aka \Microsoft Malware Protection Engine Denial of Service Vulnerability\ a different vulnerability than CVE-2017-8535 CVE-2017-8536 CVE-2017-8539 and CVE-2017-8542.