Windows Point-to-Point Protocol over Ethernet (PPPoE) 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 take additional actions prior to exploitation to prepare the target environment.

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

Security updates
10.0.17763.4131 — https://support.microsoft.com/help/5023702
10.0.20348.1607 — https://support.microsoft.com/help/5023705
10.0.20348.1602 — https://support.microsoft.com/help/5023786
10.0.19042.2728 — https://support.microsoft.com/help/5023696
10.0.22000.1696 — https://support.microsoft.com/help/5023698
10.0.22621.1413 — https://support.microsoft.com/help/5023706
10.0.10240.19805 — https://support.microsoft.com/help/5023713
10.0.14393.5786 — https://support.microsoft.com/help/5023697
6.0.6003.21966 — https://support.microsoft.com/help/5023755
6.0.6003.21966 — https://support.microsoft.com/help/5023754
6.1.7601.26415 — https://support.microsoft.com/help/5023769
6.1.7601.26415 — https://support.microsoft.com/help/5023759
6.2.9200.24168 — https://support.microsoft.com/help/5023756
6.2.9200.24168 — https://support.microsoft.com/help/5023752
6.3.9600.20865 — https://support.microsoft.com/help/5023765
6.3.9600.20865 — https://support.microsoft.com/help/5023764