Is it possible for a C#/VC++ application running in System context to access user context for NTLM/Kerberos authentication?

No, it is not possible for an application running in the System context to directly access the user context for NTLM/Kerberos authentication. The System context is a highly privileged context that runs without any user-specific information or credentials.

NTLM and Kerberos authentication rely on the user's credentials and security context to perform authentication. In the System context, there is no direct access to user-specific information or credentials. Therefore, an application running in the System context cannot authenticate as a specific user or access user-specific resources using NTLM/Kerberos authentication.

If you need to perform operations in the user context, you would typically need to run the application with the user's credentials or establish a separate communication channel between the application running in the System context and the user's context to perform the required operations.

It's worth noting that accessing user-specific information from the System context can raise security concerns, as it may violate the principle of least privilege. Care should be taken when designing and implementing such scenarios to ensure proper security measures are in place.