Microsoft Brokering File System Elevation of Privilege Vulnerability

According to the CVSS metric, the attack complexity is high (AC:H). What does that mean for this vulnerability?
Successful exploitation of this vulnerability requires an attacker to win a race condition and also to take additional actions prior to exploitation to prepare the target environment.

What privileges could be gained by an attacker who successfully exploited the vulnerability?
An attacker who successfully exploited this vulnerability could gain the ability to create or open a new registry key without enforcing access checking.

According to the CVSS metric, successful exploitation could lead to a scope change (S:C). What does this mean for this vulnerability?
In this case, a successful attack could be performed from a low privilege AppContainer. The attacker could elevate their privileges and execute code or access resources at a higher integrity level than that of the AppContainer execution environment.

Security updates
10.0.25398.830 — https://support.microsoft.com/help/5036910