NT IIS IISAPI Extension Enumerate Root Web Server Directory Vulnerability

Bugtraq ID:	194
Class:	Configuration Error
CVE:	CVE-1999-0450
Remote:	Yes
Local:	Yes
Published:	Jan 26 1999 12:00AM
Updated:	Jul 11 2009 12:16AM
Credit:	This vulnerability was first posted to the NTBugtraq mailing list by David Litchfield (Mnemonix).
Vulnerable:	Microsoft IIS 5.0 - Microsoft Windows 2000 Advanced Server SP2 - Microsoft Windows 2000 Advanced Server SP2 - Microsoft Windows 2000 Advanced Server SP1 - Microsoft Windows 2000 Advanced Server SP1 + Microsoft Windows 2000 Advanced Server + Microsoft Windows 2000 Advanced Server - Microsoft Windows 2000 Datacenter Server SP2 - Microsoft Windows 2000 Datacenter Server SP2 - Microsoft Windows 2000 Datacenter Server SP1 - Microsoft Windows 2000 Datacenter Server SP1 - Microsoft Windows 2000 Professional SP2 - Microsoft Windows 2000 Professional SP2 - Microsoft Windows 2000 Professional SP1 - Microsoft Windows 2000 Professional SP1 + Microsoft Windows 2000 Professional + Microsoft Windows 2000 Professional - Microsoft Windows 2000 Server SP2 - Microsoft Windows 2000 Server SP2 - Microsoft Windows 2000 Server SP1 - Microsoft Windows 2000 Server SP1 + Microsoft Windows 2000 Server + Microsoft Windows 2000 Server Microsoft IIS 4.0 + Cisco Building Broadband Service Manager (BBSM) 5.0 + Cisco Building Broadband Service Manager (BBSM) 5.0 + Cisco Call Manager 3.0 + Cisco Call Manager 3.0 + Cisco Call Manager 2.0 + Cisco Call Manager 2.0 + Cisco Call Manager 1.0 + Cisco Call Manager 1.0 + Cisco ICS 7750 + Cisco ICS 7750 + Cisco IP/VC 3540 Video Rate Matching Module + Cisco IP/VC 3540 Video Rate Matching Module + Cisco Unity Server 2.4 + Cisco Unity Server 2.4 + Cisco Unity Server 2.3 + Cisco Unity Server 2.3 + Cisco Unity Server 2.2 + Cisco Unity Server 2.2 + Cisco Unity Server 2.0 + Cisco Unity Server 2.0 + Cisco uOne 4.0 + Cisco uOne 4.0 + Cisco uOne 3.0 + Cisco uOne 3.0 + Cisco uOne 2.0 + Cisco uOne 2.0 + Cisco uOne 1.0 + Cisco uOne 1.0 + Hancom Hancom Office 2007 0 + Hancom Hancom Office 2007 0 + Microsoft BackOffice 4.5 + Microsoft BackOffice 4.5 + Microsoft Windows NT 4.0 Option Pack + Microsoft Windows NT 4.0 Option Pack Microsoft IIS 3.0 - Microsoft Windows NT 4.0 SP6a - Microsoft Windows NT 4.0 SP6a - Microsoft Windows NT 4.0 SP6 - Microsoft Windows NT 4.0 SP6 - Microsoft Windows NT 4.0 SP5 - Microsoft Windows NT 4.0 SP5 - Microsoft Windows NT 4.0 SP4 - Microsoft Windows NT 4.0 SP4 - Microsoft Windows NT 4.0 SP3 - Microsoft Windows NT 4.0 SP3 - Microsoft Windows NT 4.0 SP2 - Microsoft Windows NT 4.0 SP2 - Microsoft Windows NT 4.0 SP1 - Microsoft Windows NT 4.0 SP1 - Microsoft Windows NT 4.0 - Microsoft Windows NT 4.0 Microsoft IIS 2.0 + Microsoft Windows NT 4.0 + Microsoft Windows NT 4.0
Not Vulnerable:

NT IIS IISAPI Extension Enumerate Root Web Server Directory Vulnerability

A GET request that specifies a nonexistent file with an IISAPI-registered extension (ie .pl, .idq) will cause the IIS server to return an error message that includes the full path of the root web server directory.

This can happen if the file is referenced as the target of the GET or passed in a variable to a script that looks for the file.

Example:

CGI Error The specified CGI application misbehaved by not returning a complete set of HTTP headers. The headers it did return are: Can't open perl script "C:\InetPub\scripts\ bogus.pl": No such file or directory

NT IIS IISAPI Extension Enumerate Root Web Server Directory Vulnerability

see discussion

NT IIS IISAPI Extension Enumerate Root Web Server Directory Vulnerability

Solution:
In IIS4 and above, you can configure it to check for the existence of a file before it returns an error message.

In IIS4:
Preferences -> Home directory -> Application
select "Check if file exists" for all IISAPI mappings registered

Also, remove all unused mappings.

NT IIS IISAPI Extension Enumerate Root Web Server Directory Vulnerability

References: