Vulnerability Note VU#242891

Microsoft Internet Explorer may handle certain web pages in an incorrect, less restrictive security zone (MS02-023)

Original Release date: 26 Aug 2002 | Last revised: 26 Aug 2002


Microsoft Internet Explorer (IE) may handle malformed Internet pages accessed through the NetBIOS protocol as if they belong to the IE's Intranet or Trusted Sites security zones, instead of the more restrictive Internet security zone.


If a user views a page on the Internet that has been malformed in a certain way to exploit the client's particular configuration, then IE may render the page using the less restrictive security settings of the Intranet zone or the Trusted Sites zone. This vulnerability cannot be exploited unless the user views the page using the NetBIOS protocol instead of HTTP.


A malicious web page may be rendered on the client host using less restrictive security settings than are appropriate for Internet pages. The specific impacts depend on the privileges specified in the client's settings for the Intranet and Trusted Sites zones.


Apply a patch from your vendor

See Microsoft Security Bulletin MS02-023 for more information:

Disable NetBIOS access to external networks.

Systems Affected (Learn More)

VendorStatusDate NotifiedDate Updated
Microsoft CorporationAffected30 May 200204 Jun 2002
If you are a vendor and your product is affected, let us know.

CVSS Metrics (Learn More)

Group Score Vector
Base N/A N/A
Temporal N/A N/A
Environmental N/A N/A



Thanks to Microsoft for reporting this vulnerability.

This document was written by Shawn Van Ittersum.

Other Information

  • CVE IDs: CAN-2002-0190
  • Date Public: 15 May 2002
  • Date First Published: 26 Aug 2002
  • Date Last Updated: 26 Aug 2002
  • Severity Metric: 2.99
  • Document Revision: 16


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