Windows Input Method Editor (IME) Elevation of Privilege Vulnerability

What privileges could be gained by an attacker who successfully exploited the vulnerability?
An attacker could use this vulnerability to elevate privileges from a Low Integrity Level in a contained ("sandboxed") execution environment to a Medium Integrity Level or a High Integrity Level.
Please refer to AppContainer isolation and Mandatory Integrity Control for more information.

According to the CVSS metric, a successful exploitation could lead to a scope change (S:C). What does this mean for this vulnerability?
This vulnerability could lead to a contained execution environment escape. Please refer to AppContainer Isolation for more information.

How could an attacker exploit this vulnerability?
To exploit this 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.

Security updates
10.0.17763.7558 — https://support.microsoft.com/help/5062557
10.0.20348.3932 — https://support.microsoft.com/help/5062572
10.0.19044.6093 — https://support.microsoft.com/help/5062554
10.0.22621.5624 — https://support.microsoft.com/help/5062552
10.0.26100.4652 — https://support.microsoft.com/help/5062553
10.0.25398.1732 — https://support.microsoft.com/help/5062570
10.0.10240.21073 — https://support.microsoft.com/help/5062561
10.0.14393.8246 — https://support.microsoft.com/help/5062560
6.2.9200.25573 — https://support.microsoft.com/help/5062592
6.3.9600.22676 — https://support.microsoft.com/help/5062597