The Winmsdp.exe sample file in IIS 4.0 and Site Server 3.0 allows remote attackers to read arbitrary files.

IIS does not properly canonicalize URLs, potentially allowing remote attackers to bypass access restrictions in third-party software via escape characters, aka the "Escape Character Parsing" vulnerability.

IIS 4.0 and Site Server 3.0 allow remote attackers to read source code for ASP files if the file is in a virtual directory whose name includes extensions such as .com, .exe, .sh, .cgi, or .dll, aka the "Virtual Directory Naming" vulnerability.

When IIS is run with a default language of Chinese, Korean, or Japanese, it allows a remote attacker to view the source code of certain files, a.k.a. "Double Byte Code Page".

Denial of service in IIS 4.0 via a flood of HTTP requests with malformed headers.

Race condition in the SSL ISAPI filter in IIS and other servers may leak information in plaintext.

The Remote Data Service (RDS) DataFactory component of Microsoft Data Access Components (MDAC) in IIS 3.x and 4.x exposes unsafe methods, which allows remote attackers to execute arbitrary commands.

IIS 3.x and 4.x does not distinguish between pages requiring encryption and those that do not, which allows remote attackers to cause a denial of service (resource exhaustion) via SSL requests to the HTTPS port for normally unencrypted files, which will cause IIS to perform extra work to send the files over SSL.

The Sun HotSpot Performance Engine VM allows a remote attacker to cause a denial of service on any server running HotSpot via a URL that includes the [ character.

In IIS and other web servers, an attacker can attack commands as SYSTEM if the server is running as SYSTEM and loading an ISAPI extension.