This can show up in a security scan of web applications, i.e. Acunetix.
This is a config problem in IIS.
There is a way to disable Windows 8.3 short name creation.You can create a registry key named NtfsDisable8dot3NameCreation in HKLMSYSTEMCurrentControlSetControlFileSystem and set it to 1. That should disable short names creation. Refer to this Microsoft TechNet article to read more about the solution.