Detailed write ups:
Microsoft Internet Explorer Invalid ContentType May Disclose Cache Directory Location to Remote Users
SecurityTracker Alert ID: 1008293
CVE Reference: GENERIC-MAP-NOMATCH
Date: Nov 26 2003
Impact: Disclosure of system information, Disclosure of user information
Exploit Included: Yes
Version(s): 6 SP1, possibly earlier versions
Description: A vulnerability was reported in Microsoft Internet Explorer (IE) in the processing of ContentType headers. A remote user can determine the location of the cache directory, which may facilitate various exploits.
It is reported that a remote user can act as a web server and return a specially crafted HTTP response to cause the connected IE browser to open a file in the cache directory with Internet zone security restrictions. The report indicates that when the ContentType is invalid and the filename has the 'htm' file extension, the browser will download the file and open the file in the cache directory. As a result, the HTML code in the file can return the location of the cache directory to the remote user.
It is reported that this exploit works on some but not all systems.
Impact: A remote user can determine the location of the target user's cache directory.
Solution: No solution was available at the time of this entry.
The author of the report indicates that you can disable Active Scripting in the Internet security zone.
Vendor URL: www.microsoft.com/technet/security/
Cause: Access control error, State error
Underlying OS: Windows (Any)
Underlying OS Comments: Tested on Windows XP
http://www.securitytracker.com/alerts/2003/Nov/1008293.html
Secunia Advisory: SA10289
Release Date: 2003-11-25
Critical: Extremely critical
Impact: System access
Exposure of sensitive information
Cross Site Scripting
Security Bypass
Where: From remote
Software: Microsoft Internet Explorer 5.01
Microsoft Internet Explorer 5.5
Microsoft Internet Explorer 6
Description:
Multiple vulnerabilities have been identified in Internet Explorer, which in combination can be exploited to compromise a user's system.
1) A redirection feature using the "mhtml:" URI handler can be exploited to bypass a security check in Internet Explorer, which normally blocks web pages in the "Internet" zone from parsing local files.
2) The above redirection feature can also be exploited to download and execute a malicious file on a user's system. Successful exploitation requires that script code can be executed in the "MyComputer" zone.
3) A cross-site scripting vulnerability can be exploited to execute script code in the security zone associated with another web page if it contains a subframe. This may potentially allow execution of script code in the "MyComputer" zone.
4) A variant of a fixed vulnerability can still be exploited to hijack a user's clicks and perform certain actions without the user's knowledge.
5) An error in the download functionality can be exploited to disclose a user's cache directory by supplying a "HTM" file extension and an invalid value in the "Content-Type:" header field. This issue does not affect all versions and may have been fixed by the latest patch for Internet Explorer.
The vulnerabilities have been reported in Internet Explorer 6.0. However, other versions may also be affected and have been added due to the criticality of these issues.
PoC exploits (Proof of Concept) are available.
Solution:
Disable Active Scripting.
Use another product.
Reported by / credits: Liu Die Yu
http://www.secunia.com/advisories/10289/

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