Remote Procedure Call Runtime Remote Code Execution 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 invest time in repeated exploitation attempts through sending constant or intermittent data.

How could an attacker exploit this vulnerability?
An unauthenticated attacker on local networks could spoof their IP address as localhost and access functionality in portmap.sys intended to only be reachable from localhost.

Security updates
10.0.17763.3406 — https://support.microsoft.com/help/5017315
10.0.20348.1006 — https://support.microsoft.com/help/5017316
10.0.20348.916 — https://support.microsoft.com/help/5017392
10.0.14393.5356 — https://support.microsoft.com/help/5017305
6.0.6003.21666 — https://support.microsoft.com/help/5017358
6.0.6003.21666 — https://support.microsoft.com/help/5017371
6.1.7601.26115 — https://support.microsoft.com/help/5017361
6.1.7601.26115 — https://support.microsoft.com/help/5017373
6.2.9200.23865 — https://support.microsoft.com/help/5017370
6.2.9200.23865 — https://support.microsoft.com/help/5017377
6.3.9600.20571 — https://support.microsoft.com/help/5017367
6.3.9600.20571 — https://support.microsoft.com/help/5017365