Administrators Configuration Manager-a server role is known Fallback Status Point (briefly: FSP). This is a somewhat controversial role. On the one hand, it gives insight into client installation errors that we would otherwise have to look for in the logs of individual workstations; on the other hand, we don't like unencrypted communications, especially ones that don't require any authentication.
It is worth checking what the would-be (because not fully installed) customer is actually communicating Configuration Manager-a and assess the extent to which such communications can contribute to increasing online risks.
For experimental purposes, the role of FSP was placed on a dedicated server (to more easily separate network communications), while the potential client is a machine running outside the domain (so that it has no chance to read configuration information from AD).
An attempt to install the client used locally copied installation files, but stripped out most of the additional installation files (what remained were ccmsetup.exe and client.msi). In addition, the following was indicated fake Management Point, but a real FSP server. Of course, the installation of the CM client fails, as shown in the fragment of the client installation log:
The client machine in this situation sends to the server FSP simple message via http protocol (without any authentication)
If you look at the contents of the package that is most interesting in this communication, you will see the following data:
Now you can compare the information transmitted over the network with the files deposited in the OUTBOX directory of the FSP server:
It is quite easy to see that the file names contain the MAC address of the "sender" and the GUID (both parameters are included in the network transmitted message). Opening a file with a GUID value that matches the captured packet reveals:
Inside the file you will find:
- NetBIOS name of the client computer (WIN-S1313FQ854K).
- MAC address (00-0C-29-78-B6-34)
- Code page (852)
- Default value of the system language identifier - LCID (1045)
- Registered error code (0x0)
- CM client version (5.0.8692.1007)
One may wonder whether transmitting such data over a network exposes computers to threats. Arguably, similar data would be obtained by scanning the network, which in many cases can be as risky an activity as eavesdropping on packets on the network.