CVE-2020-1055: Microsoft Windows 10

Medium severity, CVSS 5.5. EPSS: 2.5% chance of exploitation in the next 30 days.

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.

Affected products

• Microsoft Windows 10: version 1809 only; version 1903 only; version 1909 only
• Microsoft Windows Server 2016: version 1903 only; version 1909 only
• Microsoft Windows Server 2019: affected versions not specified

Published 2020-05-21. Last modified 2026-08-19.