An elevation of privilege vulnerability exists in Windows Media Service that allows file creation in arbitrary locations. To exploit the vulnerability, an attacker would first have to log on to the system. An attacker could then run a specially crafted application that could exploit the vulnerability and take control of an affected system. The update addresses the vulnerability by correcting how the Windows Media Service handles file creation.
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-1068
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2020-1068