The URL parser in Microsoft Internet Information Services (IIS) 5.1 on Windows XP Professional SP2 allows remote attackers to execute arbitrary code via multiple requests to ".dll" followed by arguments such as "~0" through "~9", which causes ntdll.dll to produce a return value that is not correctly handled by IIS, as demonstrated using "/vtibin/.dll//~0". NOTE: the consequence was originally believed to be only a denial of service (application crash and reboot).

Microsoft Internet Information Services (IIS) 5.1 permits the IUSRMachine account to execute non-EXE files such as .COM files, which allows attackers to execute arbitrary commands via arguments to any .COM file that executes those arguments, as demonstrated using win.com when it is in a web directory with certain permissions.

The WebDAV extension in Microsoft Internet Information Services (IIS) 5.1 and 6.0 allows remote attackers to bypass URI-based protection mechanisms, and list folders or read, create, or modify files, via a %c0%af (Unicode / character) at an arbitrary position in the URI, as demonstrated by inserting %c0%af into a "/protected/" initial pathname component to bypass the password protection on the protected\ folder, aka "IIS 5.1 and 6.0 WebDAV Authentication Bypass Vulnerability," a different vulnerability than CVE-2009-1122.

Microsoft Internet Information Server (IIS) 5.1 allows remote attackers to view path information via a GET request to (1) /vtipvt/access.cnf, (2) /vtipvt/botinfs.cnf, (3) /vtipvt/bots.cnf, or (4) /vtipvt/linkinfo.cnf.