Information
The Common Information Model (CIM) system allows for hardware-level management from remote applications through standard APIs. Ensuring only minimal access necessary to these applications is imperative to prevent potential security compromises. A dedicated service account, specific to each CIM application, should be created to limit access and privileges.
Restricting access to CIM services is essential to prevent unauthorized or over-privileged access, which could lead to potential security vulnerabilities. This practice adheres to the principle of least privilege, promoting a more secure environment.
NOTE: Nessus has not performed this check. Please review the benchmark to ensure target compliance.
Solution
To limit CIM access, perform the following:
- Create a limited-privileged service account for CIM and other third-party applications.
- This account should access the system via vCenter.
- Give the account the CIM Interaction privilege only. This will enable the account to obtain a CIM ticket, which can then be used to perform both read and write CIM operations on the target host. If an account must connect to the host directly, this account must be granted the full "Administrator" role on the host. This is not recommended unless required by the monitoring software being used.
Alternately, run the following PowerCLI command:
# Create a new host user account -Host Local connection required-
New-VMHostAccount -ID ServiceUser -Password <password> -UserAccount
Impact:
If improper access is granted to CIM-based hardware monitoring tools or other third-party applications, they may not function as expected or could be exploited to compromise the host's security.