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.

Pi3Web web server 2.0.2 Beta 1, when the Directory Index is configured to use the "Name" column and sort using the column title as a hyperlink, allows remote attackers to cause a denial of service (crash) via a malformed URL to the web server, possibly involving a buffer overflow.