Windows CNG Key Isolation Service 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.

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

Security updates
10.0.17763.4252 — https://support.microsoft.com/help/5025229
10.0.20348.1668 — https://support.microsoft.com/help/5025230
10.0.19042.2846 — https://support.microsoft.com/help/5025221
10.0.22000.1817 — https://support.microsoft.com/help/5025224
10.0.22621.1555 — https://support.microsoft.com/help/5025239
10.0.10240.19869 — https://support.microsoft.com/help/5025234
10.0.14393.5850 — https://support.microsoft.com/help/5025228
6.0.6003.22015 — https://support.microsoft.com/help/5025271
6.0.6003.22015 — https://support.microsoft.com/help/5025273
6.1.7601.26466 — https://support.microsoft.com/help/5025279
6.1.7601.26466 — https://support.microsoft.com/help/5025277
6.2.9200.24216 — https://support.microsoft.com/help/5025287
6.2.9200.24216 — https://support.microsoft.com/help/5025272
6.3.9600.20919 — https://support.microsoft.com/help/5025285
6.3.9600.20919 — https://support.microsoft.com/help/5025288