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 Isapiusers.txt.