Affected: Microsoft Windows 10 Version 1809, Microsoft Windows 10 Version 1903 for 32-bit Systems, Microsoft Windows 10 Version 1903 for ARM64-based Systems, Microsoft Windows 10 Version 1903 for x64-based Systems, Microsoft Windows 10 Version 1909, Microsoft Windows Server 2019, Microsoft Windows Server 2019 (Server Core installation), Microsoft Windows Server, version 1903 (Server Core installation), Microsoft Windows Server, version 1909 (Server Core installation)

A cross-site-scripting (XSS) vulnerability exists when Active Directory Federation Services (ADFS) does not properly sanitize user inputs. An un-authenticated attacker could exploit the vulnerability by sending a specially crafted request to an affected ADFS server. The attacker who successfully exploited the vulnerability could then perform cross-site scripting attacks on affected systems and run scripts in the security context of the current user. This security update addresses the vulnerability by ensuring that ADFS properly sanitizes user inputs.