Windows Secure Socket Tunneling Protocol (SSTP) 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 win a race condition.

How could an attacker exploit this vulnerability?
An unauthenticated attacker could send a specially crafted protocol message to a Routing and Remote Access Service (RRAS) server, which could lead to remote code execution (RCE) on the RAS server machine.

Security updates
10.0.17763.3770 — https://support.microsoft.com/help/5021237
10.0.19043.2364 — https://support.microsoft.com/help/5021233
10.0.20348.1366 — https://support.microsoft.com/help/5021249
10.0.22000.1335 — https://support.microsoft.com/help/5021234
10.0.22621.993 — https://support.microsoft.com/help/5021255
10.0.10240.19624 — https://support.microsoft.com/help/5021243
10.0.14393.5582 — https://support.microsoft.com/help/5021235
6.1.7601.26266 — https://support.microsoft.com/help/5021291
6.1.7601.26266 — https://support.microsoft.com/help/5021288
6.3.9600.20721 — https://support.microsoft.com/help/5021294
6.3.9600.20721 — https://support.microsoft.com/help/5021296
6.0.6003.21815 — https://support.microsoft.com/help/5021289
6.0.6003.21815 — https://support.microsoft.com/help/5021293
6.2.9200.24018 — https://support.microsoft.com/help/5021285
6.2.9200.24018 — https://support.microsoft.com/help/5021303