vCenter Server plugins must be verified.

The vCenter Server includes a vSphere Client extensibility framework, which provides the ability to extend the vSphere Client with menu selections or toolbar icons that provide access to vCenter Server add-on components or external, web-based functionality. vSphere Client plugins or extensions run at the same privilege level as the user. Malicious extensions might masquerade as useful add-ons while compromising the system by stealing credentials or incorrectly configuring the system. Additionally, vCenter comes with a number of plugins preinstalled that may or may not be necessary for proper operation.

From the vSphere Client, go to Administration >> Solutions >> Client Plug-Ins. View the Installed/Available Plug-ins list and verify they are all identified as authorized VMware, third-party (partner), and/or site-specific approved plug-ins. If any installed/available plug-ins in the viewable list cannot be verified as allowed vSphere Client plug-ins from trusted sources or are not in active use, this is a finding.

From the vSphere Client, go to Administration >> Solutions >> Client Plug-Ins, click the radio button next to the unknown plug-in, and click "Disable". If the plugin will not be needed in the future, proceed to uninstall the plug-in. To uninstall plug-ins, do the following: If vCenter Server is in linked mode, perform this procedure on the vCenter Server that is used to install the plug-in initially and then restart the vCenter Server services on the linked vCenter Server: In a web browser, navigate to "http://vCenter_Server_name_or_IP/mob", where "vCenter_Server_name_or_IP/mob" is the name of the vCenter Server or its IP address. Click "Content". Click "ExtensionManager". Select and copy the name of the plug-in to be removed from the list of values under "Properties". Click "UnregisterExtension". A new window appears. Paste the name of the plug-in and click "Invoke Method". This removes the plug-in. Close the window. Refresh the Managed Object Type:ManagedObjectReference:ExtensionManager window to verify the plug-in is removed successfully. Note: If the plug-in still appears, restart the vSphere Client. Note: The Managed Object Browser (MOB) may have to be enabled temporarily if it was disabled previously.