Pi3Web 2.0.3 before PL2, when installed on Windows as a desktop application and without using the Pi3Web/Conf/Intenet.pi3, allows remote attackers to cause a denial of service (crash or hang) and obtain the full pathname of the server via a request to a file in the ISAPI directory that is not an executable DLL, which triggers the crash when the DLL load fails, as demonstrated using Isapi\users.txt.
Improper Input Validation The product receives input or data, but it does
not validate or incorrectly validates that the input has the
properties that are required to process the data safely and
correctly.