FAQ
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.
Mitigation
The following mitigating factors might be helpful in your situation: Setting LegacyAuthenticationLevel - Win32 apps | Microsoft Docs to 5= RPC_C_AUTHN_LEVEL_PKT_INTEGRITY might protect most processes on the machine against this attack. Note that COM does not currently have a notion of minimum authentication level if authenticated, for example it is not possible to accept calls at RPC_C_AUTHN_LEVEL_NONE or >= RPC_C_AUTHN_LEVEL_PKT_INTEGRITY (server-side concern, but mentioning for completeness as it limits configuration-based options), nor is there a way to set the client-side authentication level for a process independent of the server-side authentication level. See LegacyAuthenticationLevel for more information about this value. For information on how to set the applicable system-wide registry value see the Setting System-Wide Default Authentication Level section of Setting System-Wide Security Using DCOMCNFG.
FAQ
What privileges could be gained by an attacker who successfully exploited the vulnerability? An attacker who successfully exploited this vulnerability could gain domain administrator privileges.