Windows UI Immersive Server API Elevation of Privilege Vulnerability

What privileges could be gained by an attacker who successfully exploited this vulnerability?
An attacker who successfully exploited this vulnerability could gain SYSTEM privileges.

According to the CVSS metric, a successful exploitation could lead to a scope change (S:C). What does this mean for this vulnerability?
In this case, a successful attack could cross a session boundary. A component that runs with elevated launch permissions could be activated from a different interactive session than the one it normally runs in, such as in a multi-user or Remote Desktop Services (RDS) deployment, allowing an attacker in one session to affect resources belonging to another user's session.

Security updates
10.0.17763.9376 — https://support.microsoft.com/help/5126651
10.0.20348.5761 — https://support.microsoft.com/help/5126655
10.0.19044.7807 — https://support.microsoft.com/help/5126657
10.0.26100.33650 — https://support.microsoft.com/help/5126646
10.0.26200.9711 — https://support.microsoft.com/help/5127648
10.0.22631.7652 — https://support.microsoft.com/help/5126653
10.0.28000.3231 — https://support.microsoft.com/help/5127646
10.0.14393.9612 — https://support.microsoft.com/help/5126868
6.2.9200.26434 — https://support.microsoft.com/help/5126835
6.3.9600.23470 — https://support.microsoft.com/help/5126836