Microsoft » Commercial Internet System » 2.5 : Security Vulnerabilities, CVEs,

IIS 4.0 and 5.0 does not properly perform ISAPI extension processing if a virtual directory is mapped to a UNC share, which allows remote attackers to read the source code of ASP and other files, aka the "Virtualized UNC Share" vulnerability.

Microsoft Commercial Internet System (MCIS) IMAP server allows remote attackers to cause a denial of service via a malformed IMAP request.

Microsoft Site Server and Commercial Internet System (MCIS) do not set an expiration for a cookie, which could then be cached by a proxy and inadvertently used by a different user.

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.

IIS FTP servers may allow a remote attacker to read or delete files on the server, even if they have "No Access" permissions.