Windows Input Method Editor (IME) in Windows 8.1, Windows Server 2012 Gold and R2, Windows RT 8.1, Windows 10 Gold, 1511, 1607, and 1703, and Windows Server 2016 allows an remote code execution vulnerability when it fails to properly handle objects in memory, aka "Windows IME Remote Code Execution Vulnerability".
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2017-8591